My (hopefully) very last post in this thread. Its not another still got the problem post.
I have fixed it!
I posted in the Tech Support forums to see if anyone there may have a fix and to my surprise there was.
The cause was because I had two different types of Memory in. So I removed the one the computer came with and kept the 2GB in. Lost a bit of speed but for no more freezing I think its worth it. I find it that it freeze crashes if my computer gets very hot but I can avoid that problem.
Maybe this could fix DooMike's problem and anyone else that may encounter this.
I had another problem with playing online but also fixed. A chkdsk /f in cmd fixed it.
Anyway thought I let you lot know that it is fixed
I can now play games without worrying. Unless it gets hot
Maybe now is a good time to reinstall STALKER.