virus

First of all, I do not understand computers, other than E mail and logging on Daves Garden and a few others. I don't understand what files are except a seed file which my daughter put in for me and I do have trouble accessing that. Anyhow, Norton started grinding away for an hour or so, then I got a sign saying it found a virus. "JS Exception Exploit". Norton put it in quarantine. It said to get rid of it, to "replace with an unaffected copy of a file and scan again". I don't know anything about putting things in files. Do I have to leave it in quarantine forever or can it be deleted?. I tried to find out from Norton, but it didn't want to answer. I feel like ringing a leper bell! I don't want that thing in my machine! Can anyone tell me gently what to do? Doris