Yeah, Vista is a little bit unstable.
I myself use WIN XP Professional and it works well.
But I don't think IE 6 or 7 is safer than Firefox 2.0.
I use FF since Firefox 1.0 and it works fine.
You should use the right extensions and it will be much safer than IE.
Advantages are Pop-up Blocker, Tab Browsing (much better than that IE7 has copied), and you can upgrade it with extensions to whatever you like.
I have never had any probs with viruses or spyware, but you should use the right software to handle that stuff.
Surfing for Pr0n is much more dangerous to get infected by those things than normal surfing.
With Spybot, SpywareBlaster, Ad-Aware, and a good Anti-Virus Software you shouldn't have any probs anymore.
Here are the links, all Freeware:
Spybot Search & Destroy
SpywareBlaster
Lavasoft Ad-Aware
I agree with you to reset your system. It will be the best. And your computer will run much faster
Monkey D. Ruffy