Help with viruses

[ppjt]

Well, I was downloading music, and then a random thing wants access to the internet. i block it, and go on with my routine. Then, i decide i may aswell scan it, so i down load a new scanner and scan, and all-of a sudden theres 335 viruses on my pc. the original seems to be called worm/vb(?).cc So, could someone explain to me what a worm, a 'dialler' and a trojan horse is, and if there is still any risks after removing all these.

 

 

 

Thanks, Paul