K, all you puter experts...I need a little advice...My computer got a Trojan Virus, don't ask how

... and it's effecting my desktop. Norton has deleted the files but I'm still getting 4 popups saying files can't be found..blah blah blah...well, I'm backing up everything so we can reformat my computer and start fresh. My question is, will I lose all of my yahoo, hotmail, outlook emails/addys or are they safe? I'm a packrat when it comes to emails and there's really too many to try to save, so I'm trying to make sure they're safe before I reformat. Another question is, how can I make sure I save everything needed to reinstall yahoo messenger, ICQ, and MSN messenger and will all of my contacts be saved as well? Any and all help will be appreciated!!!