Hi,
I am yet to try this, but in the dllcache dir edit the filelist.xml to
remove the GDB reference and then save it. else where delete the
filelist.xml file and then (in theory) bingo, no system restore on gdb
files.
I hope it works as I've upgraded my machine to XP and find it annoying.
If this works, it can work for any file type you like.

Richard Pendered