Watching Videos Crashes Computer?

bought a pre-made from computer from tiger electronics last year in june.immediately, as in the day i got it, i started crashing when opening Internet.i solved that by turning off the realtime visualization or something along those lines and it was temporarily fixed. i began to have more start up problems and other stupid issues with the computer and their tech-support insisted that nothing was wrong and i'm an idiot but to satisfy me they'd change my hard drive. so that did nothing, and unless i want to pay a bunch for them to do a real check up on it i've been screwed. whenever i open a video, from windows media player to my flip video camera player my computer will instantly crash. whether it's a blue, green, white, or black screen it's different every time.