Bought the deluxe GOTY edition on steam a couple days ago, and the game crashes right after right after I hit play on the launcher. Sometimes I get the Bethseda screen if I'm lucky before the generic "Oblivion has stopped working" error message, with no details or options to do anything but close. I've tried all sorts of combinations of running the program in administrator/compatibility modes. I'm on a brand new pc, got all my most recent drivers, have no idea what the problem could be. Here are my specs:
Win7 build 7600, AMD Athlon II x4 635, ATI HD 5770
Any ideas, you technological wizards?

Maybe the download was corrupted (happened to me with Gmod), try verifying the game cache using steam. I think you have to right click on Oblivion then click Properties and the Verify Game Cache should be there. Hope this helps!