I'm running in window mode but can't resize the window at all. Tried adjusting resolution to half my native and yet it still fills the screen in windowed mode (minus the task bar which is still there).
For the OP, there's a good tool (it's free) called EVGA Precision, that you can have display your GPU temps in-game, much like FRAPS displays your FPS. You can also use it to display your FPS if you want too.
NOTE: Many games that run PunkBuster will kick for running EVGA Precision. So if you use it on other games and get kicked, then you know why.