Thanks for letting us know the the specs are correct.
Is it that you can not open/Play Sims 3 or that you can't open that particular saved game?
Would you mind maybe doing a test for us? If you're able to play the game. Create a new game in say Sunset Valley. For sake of a quicker test, pick a family out of the household Library. Play them for awhile and then Save As. If it goes well, play that family again. Save As again
I'm hoping this will give us an idea if your previous game save is corrupted some how.
MrsFlynn