I put Department store, last year it looks like kmart got most of my money because of the clearances lol. But it can vary:
I actually like walmart because they do not badger customers into buying extra things and the electronics dept. is stocked with many staff close at hand. 90 day return policy on video game hardware, can't find that anywhere else for free, and also they take almost anything back as long as you keep the reciept! And you will never have to worry about buying new games as used there, or have to worry about re-shrinkwrapped games. Kmart and target's electronic dept's are staffed very poorly, and the only time I will go out of my way to track down an employee is for those kmart clearance games.... lol.
I will forever avoid best buy because their entire principle is to sell you items at an amazing markup and to get as much out of you as possible while in the store by having employees hassle you when you are just trying to buy an item and leave the store as fast as possible. I do not like to be hassled to buy extra things I do not need while shopping. Yes I reallize this is the fault of management and not the front end employees.
The Ebgames by my house is very good, but I usually go there for preorders only though, and the very very occasional used game (maybe like 2-3 games a year).
Gamecrazy is horrid because the one time I went to one they tried to hire me, so I will NEVER set foot inside their stores again, plus they are not very close to me so this makes avoiding them easy. They are also 100 times worse at badgering the customers to buy extras and to sign up for the mvp card than ebgames will ever be, at least for the store closest to my house, where I do not seem to have a problem with getting asked to buy extra's at all. Their employees are just downright annoying, and act exactly like that training video that was posted on the internet.