Win 7 and apps
My old laptop overheated regularly, and shut down because the heat sink compound had been forgotten. Since then, I run a nifty utility called Notebook Hardware Control, which puts a little icon with CPU temperature in the taskbar.
With Win 7, it wouldn't start at boot time. I've just solved the problem: I turned off User Account Control and all is well. UAC isn't actually about User Accounts, as far as I can see: it's about stopping software from working.
So if you have problems with stuff not running, try turning off UAC.