I didn't quite understand everything you just said, but if I'm interpreting correctly, Norton found a virus somewhere in your system restore files and you're asking if it's safe to get rid of the system restore files. If that is the case, the answer is yes, it is perfectly safe and probably recommended to delete the files, as your system restore data might have been infected by the virus at this point. All you will lose is the ability to restore your system to any point in time earlier than when you erase the files. I am assuming you're using the Windows XP System Restore, as that is the only one I'm familiar with, but I believe the System Restore on newer Windows systems works somewhat the same.
EDIT: Just read the information on the Norton website. Yes, it's safe. Updating your virus definitions will keep you protected against new viruses. Updating Norton will just give you a newer version of Norton. Though that usually includes that virus definitions that were up to date at the building of that version, it's best to update them even after you download a new version, as they are updated almost daily.
Also, it's not really any of my business, but if it were my computer, I'd choose a different virus scanner. Norton takes more system resources than necessary and has a few other issues.