Is this file a virus?

Ive run a scan with Trend Micro Titanium 2 times now, but it doesn't seem to get rid of it. Anyway, I have the "isass" virus file in the program files area, and I deleted it but a website that I went to told me that in order to completely get rid of it, I had to find it in the system 32 folder (which I didn't find it in) and then do a serach in the registry by running regedit. Anyway, I ran that and then did a search of "isass" in it, and it found one file called "(Default) REG_SZ" So do I delete that file? I am very nervous of deleting a file in the registry, so any help would be appreciated.