For some reason, lately the computer has been acting real slow to open programs or explorer windows, and seems to give me the 'Program not responding' message every so often. If I do see the 'Not responding' message, how do I end the application or t ask (CTRL-ALT-DEL doesnt do anything), because once the 'Not responding' message shows up, the computer stops responding to keyboard input while the mouse still works.
Above all, why is this happening and how to fix it