I expect a lot depends on whether you have backups of the computer which would let you wipe the problem and replace it with a recent copy of the system from before the virus got hold.
If you have backups, your strategy could then depend on whose backup software you are using.

If you don't have backups organised, you ought to do so as soon as you have solved this current problem.
I use and thoroughly recommend onc called Acronis True Image, which will make a "snapshot" copy of a whole partition at a specific point in time. When your system goes kaput, you can boot from a CD which allows you to restore the snapshot and it just overwrites the trashed partition with what was there at the time of the snapshot.
I think I saw it on one of this month's computer magazine cover disc giveaways, so a trip to a bigger newsagents might be worthwhile.

Hope you get it sorted.
Quack!
Geoff.