Help! Please!

Hi!  I woke up this morning with all kinds of havoc happening on my computer.  Norton has scanned it and keeps coming up with packed.generic.200 virus that it cannot remove.  I have tried everything to get rid of it and I am just at the end of my rope.  Better yet, I have Anti-virus-1 trying to download itself onto my computer and I cannot view a lot of pages.  It either tells me that view that page or it redirects me.  I have never had any problems with viruses before and I would appreciate some help.  Thanks so much in advance!