PS3 should be 50/60Hz machine. Region locked games are extremely rare, older platform games not working properly would have more to do with emu settings (config).
Both x360 and Wii are 50/60Hz as well, although Wii sometimes needs some method of forcing to get some games to work and x360 you need jtag/rgh to have full region free.

If the PS3 is behaving like that, the check list:

Open up and give it a clean... don't go as far as replacing thermal paste for this job.
PSU might be getting tired. Old fats can work ok for PS3 games, mostly, but some PS2 games can be demanding so the PSU gets pushed.

After that things get beyond easy.
Even the PSU issue can be a pain if you don't have a spare to swap in... although I seem to recall a tutorial years ago about frankenPSU using PC PSU anything like that is ugly though as it's an externalised mod.