250GB.
It's a racket just like phone companies who offer some minuscule amount of texts and then the next package up is a bajillion texts.
4GBs is not nearly enough to do anything and 250 is far more than you'll need.
I have at most 4 games in rotation. If I'm done playing a game, I delete the disc from the HD and keep the files.
If you want to watch movies from ZUNE and have the 4GB, I believe streaming will be your ONLY option. Kinda sucks because if you start the movie download early on, you can 1080P video later without potential streaming adjustments.
But, I wonder. I know you can attach an external HD to an Xbox and use it as a storage spot but only up to 16GBs. I wonder if you could partition a 1TB HD into however many 16GB partitions it would be and use each partition individually. It would probably take a decade to set up but that might be an option if you have no others.