How do I know some games work?

One time i got call f duty and installed it and played it a few times but then something changed. The screen became very bright and you could barely see anything, and it wasn't the brightness. I took it to a proffetional he didn't know so I restored my computer, now i dont want to have that problem again...

I have windows vista premium and i wanna know how do i know if a game will work and nothing go wrong. ( like the video card and Ghz and all that stuff i dont understand) I also wanna know how i can check to see those things on my computer ( windows vista premium)How do I know some games work?
If you are buying games then it will always have a minimum spec on the rear of the case. You must always read this before you buy the game because it is not refundable if it is not compatable because the compatability is there for all to read so if you buy it you have to make sure it will run on your system firstHow do I know some games work?
okay,it is important that you know you system's info.Your pc has to meet the requirements in order for the game to work properly.You should be able to find your system info in the control panel.It usually is the problem though.