iMac Crashing when booting up

[PC-M Vip3r]

Last few weeks my iMac has been crashing when booting up, sometimes it crashes when osx has loaded up and the desktop appears and sometimes it crashes before. It can take 3 o 4 attempts to get it to load up without crashing.

The weird thing is, once it has loaded up without crashing it's fine, it's not crashed once when its actually on.

Any ideas?

 

[PC-M Vip3r]

Got a crash log we can have a look at?

How do I find one of them?

 

[PC-M Vip3r]

The only things in startup are Itunes Helper and EyeTV Helper.

No kernal panics or any error massages it just freezes when booting or as soon as it gets to the desktop.

Just tried to open console and it crashes as soon as it opens.