This could be several things. Are you able to post your setup, e.g. processor, amount of RAM etc?
Try running disk cleanup and then disk defragmenter (Accessories > System Tools).
Check the free space on your disk drive(s).
Check in task manager for processes running. There will also be quite a few, any you don't recognise Google the exe file name attached to the process, you will usually fin dsome information on what it is.
The Cornflake
August 2007