Strange computer issues.

I have been building a second pc( from parts laying around) for 3d stuff and some gaming. The next day my main machine dies, no problem i will fire up the other pc. Start up the new build and it says no os, so i grab an old copy of win7 Ulitmate and do a fresh install. Can't get on the internet, drag old linux box out and download ethernet drivers and install, now internet works. Download and install Avast, Opera, Ati drivers and they all work.

Next i install Steam and Left4Dead2 and probably spent an hour or 2 playing L4d and no problems at all.
I then install 3d Coat (3d sculpting program) and when i try to run the program it does nothing.I download Media Player Classic and some random mp4 video and when i try to play the video, it starts then crashes.Some Dx9 message appears , so i install Dx9, still have the problem.Try the built in games like Freecell and Majong, and when i click on the icon, nothing happens.

Ok, i will try to open a jpg and sure enough i get "Com surrogate has stopped working" message.
I can open it in Paint however.

Well maybe it was a bad install, so today i reinstalled Win7, and this time i deleted the 450mb OEM partition,and the other 2 partions (100mb recovery and the main part). I create a new partition and the format it twice.Installed win7 again and still have the same problems. MPC and Freecell, and Windows Photo viewer still don't work.

I have never used this Wd hard drive and the Video card before

I haven't bothered to install Avast,Steam,L4D2 or the Service Pack1.

Anybody got any ideas? I've never seen these problems before.
Thanks for your help.