Re: Which is better for gaming? *New to computers and forum*
I use mine as a DVR, and I can fit about 1500 hours of 720p television on my 2tb. If you're really just going for gaming a 128gb SSD should be enough for os and programs. If you find you need more storage you can get the platter based stuff later, but with the ssd you computer will be pretty zippy. Even if you wanted to play games stored on your computer rather than DVD, you'll have about 100 gigs to do so after accounting for the size of the os and basic programs.
Oats is probably right about the heatsink, you'll only need one if the gpu is putting out too much heat into the case, and you can always add one later if you do end up needing it. Just saying, don't forget you're going to have to cool all of this, and that a better gpu is going to put out more heat.