Welcome Torin!
I like Cakewalk for the software. Not all the home or lite versions will record more than 2 tracks at once, so look carefully before you buy.
A multiple input card for under $250? Try the
MAudio Delta 1010 LT. MAudio makes good stuff. I use the full version
Delta 1010.
For monitors, you need a set of near field reference monitors. I use the
Event 20/20bas, but there are lots. Don't skimp here. It'll be a lot harder to turn out a decent mix on lousy speakers.
Your mixer will be fine for recording 2 channels at once. It might do four at once, although monitoring will be a challenge. More than that, you'll need a new board. You want to look for a board that has direct outs on the channel strips themselves.