Game freeze problam on ps3

hi to all i just bought injustice for the ps3 and i have a slight problam.
the game freezes on the title screen and i cant get the game to load
any tips?

PSN download or Disc?

disc

Check the disc for scratches and defects. Try the game in a different PS3. If it works, you probably have some sort of issue your PS3’s optical drive.

i just deleated the game save data so now it works but connecting to lobbies takes forever
and sometimes i get an error massage telling me the servers are down.any tips?