I've been lurking around for quite a while, but finally got my courage up to writing something

I tried making some SIDs a few years back, and now I wanna havw a go at PC music. To start off with a bang I just bought myself a used Korg N5 synth, even though I don't know how to play it. I'm gonna hook it up to my computer, and that's where I'm hoping for som help from all you experienced musicians. I know squat 'bout MIDI, so I'll probably ask alot of stupid questions

First off, I'd like some opinions on my PC. It's a bit old, and I guess music stuff takes alot of resources. Specs are:
PIII 800 MHz
200 GB HD
128 MB RAM
SoundBlaster Live!
I know the soundcard is poor, but will the rest do? In particular - do I need lots more RAM? Is there a cheap sondcard that'll do a better job than the SB ones, without costing me a fortune?
Any suggestions on good music software for beginners is also very welcome. Sequencers, samplers, mastering - all these words just make my head spin at the mo', but I hope "learning by doing" is A Good Thing

Thanks in advance for any help, and cheers for all the great musc and retro nostalgia I get from R64 and RKO!.
- pfk