Hi Greenking,
How long has this been happening? If only recently, can you remember what you were doing just before the problem began? Can you pinpoint an event that coincided with the first time this happened? It's just that 'freezing' could be caused by any number of things, but it's usually either a software program fighting with another, or a glitchy piece of hardware, like a graphics card, or, as Clive said, a mouse.
This happened to me after I installed a new graphics card on my old PC, but when I put the original back in, the problem was cured.
I've just read your last post. Taking what Bat said into account, (he knows what he's talking about!), my suggestion would be to uninstall each of your recently installed programs one by one, until you come to a point where the problem is cured. You can then start to reinstall your programs, and if you keep track, you should be able to pin the cause down by a process of elimination. It also seems that you could either do with a new, bigger hard drive, or a radical clear out of your old one!!