|Avast 4 will definitely run and update on W98SE, I'm using it on my oldie.|
Some years ago they said they were intending to stop updating that version but so far it still works. Of course they could dump it any time.
I know of nothing else for W98 except some rickety old DOS AV's that do not pick up viruses but you have to scan for them - not good.
Always pop back and let us know the outcome - thanks