Yep.
When your machine freezes, I'm guessing that one particular process/program is jumping in and hogging all the processing time.
If you're running windows, press Ctrl-Alt-Delete to bring up the task manager.
In the task manager, goto the Processes tab. This will show you a list of all processes currently running on your machine, along with who's running them, how much memory they use, and a few other things.
I'd suggest you click on the CPU header at the top of the processes list. This will sort the list of processes by the % of computer's processing time they take up. You might need to click it a couple of times to get the list sort in descending order.
If you watch the list of processes, you should see the name of the process/program responsible appearing at the head of the list when your machine freezes. Take a note of its name, and google it. This should bring up a list of web pages which keep a list of what different process names are, what they do, and what programs they're associated with.
From there you can decide if the reason it's freezing is beacuse of spyware (kill it!) or some other program that you installed intentionally, and decide what steps to take from there.