graphic artifacts

Thanks for the tip, here is a screen shot of me trying to access the app folder. All of my menus are like this, I hope it's not a hardware issue, this mac has been nothing but trouble. Cheers !

Awesome thanks a lot for that great info, I hadn't thought of the permissions. I did a safe boot (all graphics are OK in safe mode) , repaired the permissions with disc utils, and rebooted the system. Now it boots fine and the graphics are displayed corectly...for a while, and then it starts to do the same thing with the video artifacts, just a little at first and then more and more, so I booted into safe mode again and repaired the permissions, same result it works and then starts to show the problem again. There is one permission that will not fix, the SUID in ARD Agent was modified but not repaired, I've looked on the boards and that seems to be a normal occurance so maybe just a coincidence. I'm starting to think it is HW issue, but I'm confused and not convinced because the problem was semi-fixed with the permissions. Any ideas?

Thanks again =)

So after about twenty hours of trouble shooting it turns out it's hardware - due to dust - lol I've cleaned out the mac in the past because it was running a little hot but this is the first time I get these funky behaviours crop up. The artifacts are not present when I run SMC fan control near maximum rpm of the fans so with your help I was able to nail the problem and will be cleaning out the beast asap haha, thanks a bunch for all your help, it was the lifeline I needed in order to persever. Thanks! and Cheers! 😎