Haha, I literally came in here ready to give a bit of a speech about the nice and powerful things you can do with the /proc pseudo filesystem, only to be greeted with this.
Basically, Linux usually will try to keep stuff in memory cached such that, if you open a program again later, chances are that disk accesses to bring up the program will be minimized or eliminated altogether.
If you are seeing crashes or freezes, I can almost guarantee that something else is causing those (could be a kernel issue or a hardware issue, that's what I've seen most commonly with Linux freezing)