Okay, so my computer crashed, failed, virused it all up. W/e you waana call it. I re-installed Vista to get rid of everything, and whola worked. No more trojans. But I noticed that I only had 140 gigs left. Odd. When it failed I had 300 gigs left. I know windows vista takes up space, but shouldn't the files just all origonally delete? then I should be set with 467 gigs, as I did when I first built my pc.
I bet that, when you re-installed VISTA, you did NOT get rid of the original install. So it's still there, taking up space, and maybe sheltering the viruses or whatever you think caused the original problem. No doubt much of that will not show up in a plain-jane directory display because system folders are hidden. If you want to try simply deleting the old folders containing the original installation, you'll need to be an administrator and have it display the hidden files and folders. Then you can TRY to delete the OLD ones only, but Windows will fight you on that.
The other alternative is to back up all your data and verify the backup, then plan to re-install EVERYTHING - OS and application software, etc. When you do the VISTA install to start, you Delete all existing Partitions, then start from scratch as if it were a completely blank new drive.