not sure if this is hardware or software, but its dam annoying either way!

when playing tf2, or css halfway through randomly it has frozen my entire computer (including the screen on my g15) both times ive been playing music on itunes

also when using itunes (i dont like wmp and use it now cos i have an iphone) the entire audio makes a screeching/grinding sound asif its being overloaded

i have a brand new i7 with 3gb ddr3 ram, im hardly overloading the cpu

do you think this could be hardware or software problem, im thinking itunes but wanna see what you guys think and to see if you have any suggestions before i ring up the makers

Call me an old fashioned iTunes-for-Windows hater, but I'd say there's an obvious starting point here....

I'm not hating but iTunes really does look to be the common thread here.

Has the issue started recently? Did it start after you installed or changed something? Are your soundcard/mobo drivers up to date?

it started recently (after the first freeze)
itunes has been the same since before these started (no updates or anything)

and it just slightly happend with no itunes, was watching an iplayer news thing, so it may or may not be itunes

and dont worry, i hate itunes, i think its slow, horribly big and totally usless, but i need it for my iphone

Have you checked that all of your drivers, (specifically the sound card) are up to date?

I would also completely shut down iTunes and not run it for a while, but give your game a try to see if it still freezes.

That's where I'd start.

on board sound
all drivers for everything else up to date
it started lagging again while watching a movie, the audio and film both lagged (best word to describe it), im thinking its the hard drive as nothing else lagged as such

running memtest to test memory and going to test the hard drive using samsungs test software, if both these says theres no problem im going to reformat. then i will know if theres a hardware fault somewhere