Today i'm going to buy A POD 2.0

But it's just dawned on me I have a crappy sound card ( Realtek AC 97)

Would everything I record sound bad?

pretty much, yes.

the weakest link in your chain is what dictates the overall quality really.
if its for recording purposes mostly, consider getting one of the line6 interfaces.
I won't change the tone of your sound so much, more the fidelity, if you know what I mean.

It definately won't make it sound so bad it's useless or anything, I would try it out and see if your think it's okay or if you want to shell out teh monely for an interface.
The thing that gets most people trying to record with cheapo soundcards is the metering and monitoring.. you can't really listen to what your reording as you record it because of the latency.. and the metering is usually so laggy and dodgey that you can't tell if you are overloading.. if you are carefull with levels you might end up being happy with the sound. but if your not happy with the sound and it is considerably different to when you listen right off your pod then definately the sound card would be a good starting point to upgrade.

stax of cheap audio interfaces.. m-audio is nice and cheap and works with pro tools which is always good.

there are heaps and alot of them are pretty good. so find a good bargain second hand or ex demo or something and your sure to be happy.

If you're looking for dirt cheap, the Behringer UCA202 is quite good. I've been using it for 6 months and although it's 16-bit, it sounds good, very little noise and practically no latency. I see no reason to change.