Antivir update 9x (personal) freezes my PC

I just updated my AntiVir and it locked up my computer when it finished. I think it was just before it would have started to scan. I'm pretty sure the installation was complete. When I click on the icon (after re-booting), I get the box with the list of drives with the AntiVir logo overlaid on it. I believe at this point, the overlay is supposed to go away, but it doesn't and I can't do anything, not even ctrl-alt-del. I'm running windows 98 and have no other anti-virus software on board. Any suggestions?