I turned off firewall, all the virus checkers and everything else. I then loaded Sims Pets.
I played for about an hour and a half when suddenly my computer screen froze. I couldn't move my mouse, or get task manager to come up. I ended up turning off my computer by the main switch.
I then turned my computer on again, and did exaclty the same, only to find that it happened all over again.. (I maybe had been playing on it longer than the first time)
It could be that your pc doesnt have alot of memory left. i know that the sim games take up alot of memory.
go to my computer then click local disk (C:) then look at details and see how much free space you have. if its under 15gb well that's probually your reason.