System restore does not lose 'saved' files or work generally speaking, so you should be ok there.
I may bang the drum a bit about computer safety but I really do think the advice and links on this thread are 100% solid.
http://cgi3.ebay.co.uk/ws/eBayISAPI.dll?ViewUs erPage&userid=cuddly-hippo
On both my pcs I am running
ZoneAlarm (firewall)
AVG
Ewido
Spywareblaster
Windows Defender
X Cleaner
Lavasoft Ad-Aware
Spybot
a-squared
I keep them all updated and those programmes that need to be ran and don't just sit in the background - I run at least once a week.
They are all free and do not conflict.
I would get rid of McAfee in all honesty.
I also have AShampoo Platimum suite - the pop up blocker is excellent.
Good luck!