Problem with multiple monitors in Media Center

My question is how to I turn off or black out one monitor and still leave the other unaffected?

I have a small 14in LCD setup as my main monitor connected via VGA and a 56in DLP at 1080p for my extended desktop connected via HDMI. Of course I want Media Center to display on the TV. Most of the time I want ONLY media center to display on the TV, but it never fails when I turn off the small monitor, to enjoy a movie in a nice dark living room, Vista tries to make the TV the main monitor. And then I have to deal with about 30 seconds of screen flashing and resizing before normal playback can resume. Is there anyway to blackout or turn off one monitor without affecting the other?

Oh yeah and here are my system specs if that helps.

Vista Ultimate x64
ATI Radeon HD 4670 512MB
4GB G-skill RAM
500GB Raid 0 HDD (2x 250GB)
AMD Athlon x2 2.8ghz sllightly overclocked to 3.1 at stock voltage
ASRock A780 motherboard

A Grate program to re leave you of your worries is Ultra Mon. It is a grate app for duel-Mon setups. You can create two personal con fig files for you monitors one TV, one Desktop. From your Quick launch you can turn off your desktop monitor(s) & enable TV form one con fig, and restore it all back to normal with the other. Plus it gives a task bar(s) to other Monitors other than primary + lots of other really useful Multiple Monitor Tools. I my self Have a quad Monitor Configration and could not get by with out this Program. Hope this helps with your problims.

Oh yeah and here are my system specs
ASUS M2N-E SLI (Moatherboard)
Vista Ultimate x64 (OS)
AMD Athlon 64 X2 2.51Ghz (Dulecore)
Nvidia 9600GT OC-X2 (SLI)
6GB Ram DDR2 667Mhz
8 HDD's Total= 3.75 TB (5 SATA- 3 IDE) 2.89TB Used
ATI HDTV All in wonder