Excuse any typos - haven't had my morning coffee yet, and neither has my spell-checker...
If you're looking specifically for "guitar effects", your best bet would be either Amplitube or Revalver - I prefer Amplitube myself as it seems a lot more professional, but - and this is a prettty big but - there's zero chance you'll be able to play it in real time with a stock (or SB) audio card - there will be a noticable delay between when you hit a note and when it sounds through your speakers. You basically have 2 choices here if you want to stay in the software realm (as opposed to buying a POD or some other hardware based solution):
1) buy a new low-latency soundcard. Cheapest one I can think of is the Audiotrax Maya44, somewhere around $100US.
2) record clean and then apply effects afterwards to your tracks. You'll have no latency (delay) as you wont be running any actual effetcs as you record, but neither will you be able to hear the effects as you play them.
Hope that helps. I opted for option 1 myself not that long ago and went with the Maya44 - again, lowest priced low-latency card I could find. Doesn't have 24/96, but that wasn't something I required - plus it's got 4 inouts to boot - too bad the mic pre-amps in the card are complete shite (good thing I have a hardware mixer for that).
Anyway, hope this was of some help. Check out the Amplitibe (
http://www.amplitube.com) and ReValver (
http://www.alienconnections.com) sites fro mp3 samples of what type(s) of sounds you can get from these programs. Again, there are other programs that do the same thing, but those 2 are my personal favorites (until
AmpFarm gets ported (yeah, right!)).