[garww]

It doesn't sound like you are in a time critical situation, so laying down tracks is not really a big deal for modest computing power.

Often more important is finding hardware with proven drivers for your operating system.

Synthetic is a good word to keep in mind. As this is digital, you have all sorts of options to synth your sound into whatever form you desire. The math takes computing power. If your doing a lot of tracks at once, you want to consider a second FAST hard drive on a separate controller for recording.

Consider that basic recording is fairly simple. Given that computers and software become outdated fairly quickly, you may want to not go overboard until you get your feet wet.

It's really apples and oranges as to Mac or PC - or Cubase or Sonar, etc.. There is plenty of capable recording software that you don't have to spend a paycheck on.