Help, Im so confused about Gamma & programs for it.

Well I guess I am just not as educated when it comes to lighting and my PC. I am looking for some software that will allow me to change the setting of my gamma not only for the games I play but even for the DVD movies I may view. Something with maybe a hot key to just change the gamma while I am in the program I need the change to take place. ]
I find software to change the games, but can't seem to find one to work with all programs even DVD movies.
I have a cheap LCD called MAG Innovision, and it has no gamma setting in the prefrences.
My video card is a PNY Verto AGP 8X GE Force- 5700 VE 256 mg DDR.
And there is some collor adjustments in there but it is to much for an amiture geek like me to figure out.
So can someone think of just a simple software that will allow me to lighten up everything. And by the way, I did a search, and I am so much of a new PC geek wannabe, I couldnt find a thing.
Thanks in advance for any help,
Danny