Personally, I would stay away from Android 4.0x, if you flash, root your phone & do a factory reset, the brickbug comes into play (4.0.4). There has also been one or two people who didn't even root their phones (allegedly) who bricked them doing a factory reset on 4.0.4.
If you must flash 4.0x, use 4.0.2/4.0.3 (I still wouldn't even do that). If you have problems with the flash, for example, bootloop - boot into recovery & do a factory reset. If that doesn't fix it, find Hopper8's 'Odin troubleshooting' thread stickied in General, download the 3 part firmware linked in the thread, and flash that with Odin (this will wipe your phone).
If you still can't get a successful flash, it might be something else fairly simple as is often the case with these, try everything in Hopper's thread. I'd be surprised if you can get a successful flash with the info in his thread, it's 'the Bible' for these things.