melzappa

I'm having major glitches on my Xbox 360 dragon born Skyrim game. Haven't downloaded any add ons or mods. Got the game from Game Stop in pretty good condition. But all of a sudden (I'm level 21) I'm getting glitches and freezes. Have to completely turn off console and start from last save. Now I've lost certain textures and things are purple. I've deleted old saves and cleared caches on my memory unit (where it's saved). I have SO MUCH space. Why isn't it working right??