The panel is sufficient for the home now. The problem with the panel is it is a Zinzco. From what I have read, it can catch fire if one of the breakers is overheated
The outlets/wire concerns me a bit more than the panel. My intention is to get the outlets/wire done in the next week or two. Then a month later, get the panel replaced.
OK, if you're only talking about a delay of a month or so, then no big deal. I'd gotten the impression that you were now considering deferring the panel indefinitely (which usually means "not until it fails catastrophically and spectacularly"

).
Your number is very correct. But my plug wires are all run in the crawl space

So down about 3 feet and then up about 2 feet but your point is well taken.
Fair enough. But the basic principle still applies -- count on using much more wire than you're currently estimating.
I'm not sure on the additional circuits yet.
If you're still figuring on a 200A panel, you will surely have WAY more than enough breaker slots to do pretty much everything you want, now or later. I still don't think you really NEED such a large (or such a high capacity) panel, in such a small house; but 200A panels are so commonly used/sold that they tend to be somewhat more cost effective than, say, even 150A panels. So if you have the physical space to accommodate such a beast, there's no really pressing reason to NOT use it.
Pardon my ignorance on this but I believe I can "split" a circuit into two assuming I run the wiring correctly. So in theory, I can maintain my current circuit count but split them apart once I swap the panel. For example, I could run two separate circuits up to a junction box(leaving a little bit of extra wire), twist the two circuits together, and output to breaker panel.
Well... Save for the fact that you've got your "ins" and "outs" turned around, that's more-or-less correct. HOWEVER... Between this, and a comment you make further down, I think there is a better way to do this. Hold that thought.
When I say fixed lights, I am referring to light fixtures on a light switch. I've got three light fixtures in the house plus 3-4 light switches. They aren't making funny noises so while I would like to replace those also, I have them lower on the list.
Ahhh... Now I understand.
{re: the welder}
You are correct. The input is around 20-30A as I've run it off a 220V drier plug and a 110V washer plug. It will pop a 15A circuit though
In which case, you really don't need to do anything very special to accommodate that welder. Now
IF you foresee upgrading it to a much higher-power model at some point... Then it would make some sense to wire for the "big gun" model when you initially do the garage, rather than have to re-do things again later.
If you do the rewire before replacing the panel, leave a couple of extra feet hanging down in that crawl space on each circuit, as you will need to route the wire different in the panel once it is replaced. Better to throw away a foot here and there than come up short. Once done with the new panel, go back in the crawl space and staple up the wires properly.
What you mention above was basically my intended route. Pull new wire as close to the panel, put a junction box, then join old wire with new wire. Make sure there is extra length so when the panel is replaced, the new wire can be pulled in.
I'm not entirely certain that you and Charles are on the same page here. So pardon me if the following seems a bit pedantic...
Siamesing multiple circuits onto a single breaker, such as you describe, would be potentially useful ONLY if you really don't have enough breaker slots in the current panel to accommodate whatever you're installing. In which case, that's another argument for replacing the panel first (or at least concurrently), and being done with it.
In most cases, the "next best" choice would be to replace a few of the existing single-gang breakers in that box with tandem-type breakers, so that each of those "slots" will support two circuits. But if you're planning to trash the panel in a month, that would be a silly waste of money.
All that said, the method you describe
IS the correct way to do such siamesing, if/when you must; but you must still observe the load limits imposed by that single breaker, even for the "temporary" lash up. And if a single (say, 15A) breaker will properly support both of those circuits when they're "siamesed" together, then there's really no point in wiring them as two separate circuits anyway, as the same will be true for the new panel as well. It would make more sense to design and install a single circuit with all devices daisy-chained conventionally, and be done with it.
In any event, you do NOT EVER attach two wires directly to a single breaker screw.
Finally
IF you do this, you should make sure you're leaving enough extra wire in each of those individual runs (i.e., before they are joined in the J-box) so that when you do finally put in the new panel, you can remove BOTH all remnants of the old "jumper" leading from the panel to the J-box AND the box itself, then connect each individual circuit DIRECTLY to its breaker in the new main panel, with no intervening junctions/splices.
Is there a best practice for securing the extra wire until the new breaker is in? I was thinking along the lines of "zig-zagging" the wire along a joist and staple the wire there.
Since this entire scheme is a kludge to start with, there's really no "Best Practice" to be had. Just be sure that you DON'T damage the jacket on the cable through over-zealous stapling, or when removing those staples when it comes time to fish the cables up to the panel.
To be up to code, am I only allowed to run a wire from the junction box then the offshoots to plugs? I thought I had read that I'm not allowed to have more than one junction box on a circuit.
I'm not sure about any hard & fast limits on the number of J-boxes ("in series", so to speak) on any given circuit. But splices and junctions are in general undesirable, and should be avoided wherever possible.. Note that it
IS standard practice to "daisy chain" a series of devices (duplex outlets, wall switches & light fixtures, etc.) together and feed them all from a single breaker/circuit, which (at least usually) inherently obviates (or at least limits) the need for separate junction boxes. Modern duplex outlets are expressly designed for this sort of installation.
FWIW - I would NOT use 20A breakers anywhere but for known large loads (e.g. kitchen or garage). The idea of a breaker is to provide protection in case of overloads and should be sized accordingly (you don't want protection from your alarm clock in your bedroom @ the same amperage as you would use to protect your home against your air compressor in your garage).
I'll second this, up to a point -- but ONLY up to a point.
Upsizing the wire itself is fine, as long as you don't get too carried away (I'd suggest AWG 12 at most for "normal" 15A lighting circuits and such), even if it is surely unnecessary in a house this small, and with wire runs as short as the OP describes. But since the breaker's ONLY "official" job is to protect that wire (and pointedly, NOT to protect whatever is plugged into the outlet), there's now really no good reason to NOT also use a 20A breaker, unless that wire run is SO long we never ever want to permit that much current to be drawn through the wire -- and in a 700 ft.^2 house, that just won't be the case.
OTOH, if we put "20A" outlets at the other end of the string, we are no longer really "upsizing" the wire at all, as it now must be expected that a 20A device WILL eventually be plugged into that outlet. So either way, I would use standard "15A" outlets and such, except perhaps in the garage.
12AWG instead of 14AWG on 15A circuits is most likely OK (less voltage drop on large loads is a good thing). Especially helpful if you are daisy chaining outlets (it's really overkill unless you have long runs).
Agreed; but again, in this particular case, it's a non-issue due to the short runs.
Be careful, though. There is a maximum number of wires you can have in an outlet box based on the size of the box, and that number drops as they get thicker (fewer wires allowed for 12AWG than 14AWG).
Someone who has a code book handy will probably cite the specifics.
Also, be careful of code issues. You cannot just assume latest NEC. State, county, and possibly city gov't's will specify what version of NEC they require, and some have additions to NEC (my county has additional requirements beyond NEC).
Good luck.
It's always good to know the rules BEFORE you start playing the game.