Before you go off buying that HDD reader, please know that you won't be able to get your game saves.
The HDD is encrypted, and each encryption key is unique to each PS3. So you can't stick your current HDD in a new PS3 and use it, it will ask you to reformat it.
There is basically no way to save your savegames unless you can turn your PS3 on somehow. Even then, you will be limited to the savegames that are unlocked. Most PS3 savegames are now locked though, to prevent people from getting trophies unfairly.
Long story short, consider your gamesaves as lost.
Awww fuckety fuck fuck fuck! I hadn't thought of that. So my only chance is fixing it. There's a data transfes feature on the PS3 though isn't there? for transfering all your data from your ols PS3 to a new one? If I buy a slim and get my phat up and running, then wouldn't that work?
I don't care about th GOWIII save, I'll happily play that again. It's the ones that take ages to unlock all the features (rock band, Guitar hero, tiger woods, Need for speed shift, etc.) that I can't be assed completing again!