Green screen Was playing fine, shut down and turned on later to play, only get green screen none of games will play

Okay, I have noooo idea what's happening...My PS3 was working perfectly fine a couple days ago, and now, it has a weird issue...When I turn it on, it looks fine(sometimes, nothing shows up), and then, when I play music, movies, view pictures, or even play games, and go on the internet, the screen gets pixelated, then green squares start appearing out of nowhere, the system freezes, and everything is useless. I've heard this issue with HD, but I'm using standard def, and I've tried everything short of taking the thing apart. Is there anything I should, or CAN do? Or should I just say "screw it", and give it to games stop? Okay, I have noooo idea what's happening...My PS3 was working perfectly fine a couple days ago, and now, it has a weird issue...When I turn it on, it looks fine(sometimes, nothing shows up), and then, when I play music, movies, view pictures, or even play games, and go on the internet, the screen gets pixelated, then green squares start appearing out of nowhere, the system freezes, and everything is useless. I've heard this issue with HD, but I'm using standard def, and I've tried everything short of taking the thing apart. Is there anything I should, or CAN do? Or should I just say "screw it", and give it to games stop?