have you defragmented your harddrive recently ?? sounds like your system is having to find the data on your harddrive perhaps....might be helpful to get you a utility like system mechanic or one I like a lot ,,,Tuneup Utilities,,,,,it will check your Programs structure for errors, registry for errors, including check your harddrive for major Fragmentation ...and has a fix it button at the end after it scans for problems and corrects them. did it start happening after a hardware or software change? how much ram do you have and speed or your processor?