Harddrive help please - Hitachi 2.5 travelstar

I have 2 identical notebooks, toshiba m105-s3041...One of them stopped working while it was on.....seemed like it locked up....In fact I had to pull the battery to turn it off....when turned on, it starts accessing the HD but never boots up....I cant go into the menus, it just locks up....HD spins and sounds fine....it was super full and I think it overfilled LOL....So i swap HD from one to the bad pc....works....HD in the good PC, it behaves same way. I cant even access the boot menu to start recovery CD. Soooo....I think the HD went bad. I need some data from it. Furthermore, I think I narrowed it to the pc board on the HD....it is keeping the systmen from accessing it....I tried putting the HD in an external enclosure (sata) and plugging USB into several PCs...nonw of them see the HD>.......I want to disassmeble the board off the drive...crazy and transplant another board from same model HD, it is a Hitachi Travelstar 80gb HD....a good idea....what size is the tiny torx screws on there....any other suggesttions? Thanks in advance

The data is valuable in that they are pics for this year, you know beach trips etc....I need a DIY solution, thanks