I can't play some of my games anymore. Would you guys have an answer?

So I downloaded RE5 recently on my ps3 and it worked just fine. I also got ff13-2 and it ran fine. but as time went by, games of mine stopped working. ultimate mvsc 3 stopped working. It appears to load, but as soon as the game should start up, the screen goes pitch black. RE5 now does the same thing. however, ff13-2 still works, as does Megaman 9 and 10.

any idea what's wrong? more importantly, what are my options?