XP slows down and hangs after a little video clip editing or moving files from one folder to another. Previously, I could select a number of files and drag them to another folder with no problems. Now only one of the selected files moves and the rest stay highlighted and the pc just sits there for a while, sometimes stopping. I use a bat file for changing attributes in a group of files and that works once and the next it hangs.

I have used Task Mgr and can't see anything hogging the mem. I have used Norton, Spysweeper and SpyBot and don't find anything. I have stripped the start menu over a period of time and nothing is creeping in.

The temperatures are all ok on the drives and cpu

What am I missing?

I would run check disk and see if it finds any problems with the hard drive.
The problems you describe could be due to a slow processor, low amount of RAM or a failing hard drive. Since you say everything worked well previously, that points at the hard drive.
I would make a complete backup of everything you need to save, because I think the hard drive is close to failing.

I found the problem, it is SpySweeper. No problem when on the net with SS but offline it it slows down and hangs my pc. The solution for me is to kill it when I am going to do photo and video editing and everything works just fine!