Updates...
Holly sh!t, man
Even as uneducated could I be with women, you did some very wrong things. I even wonder how she is with you any longer...
The part with cooking was ok. It was wrong to imply that you've cooked anything when you didn't, but it seems it went ok.
What reason do you have to take pictures? Because she is beautiful, that's the reason (and by the way, judging from the picture you took, she looks great). And don't let her win the argument (if she do so) that she isn't - after two years, you should have plenty of things you like.
While playing a game might be fun for a kid/man, watching a game is NOT. Go to a friend and ask him to play Halo for an hour, to see how much you like to look at it. As for girls, they like totally different games than boys - Diamond Mine/Bejeweled, Tetris-like maybe. Looking at someone playing a game? I did it once or twice with my fiancee (she played), but the only nice thing was to see her enjoy supermoves on Bejeweled 2.
About putting her to keep the sign up so you could take pictures? That would work in a mid-day somewhere out, not an evening - a big one at that...
Where were the flowers???????? Girls love much more flowers than looking at computer games played by someone else.
As for videos/YMMTD whatever - you should have gone to a real movie renting place and ask a lady from there to recommend you a movie to see with your gf. Something short (two hours tops, let's say). Bonus points for having several available, in case she's seen the only one you got.
Another reason against games - games take all your attention, so very little is left for the other one. How do you think she felt? Marginalised. Like she is nothing.
If you want... well... to make love to her, you should show her (more than one time) that SHE is the most important thing for you. Else, take some money and go on the roadside, you'll find a "third base" quick.
Good luck next time. If I were her, I would have left you. As for owning in Halo, she's just as impressed with that as if you would find out she is able to talk with her good friends all day long without saying something of significance (and without doing anything else).
(congratulations on Halo and WoW skills - they might be extraordinary, but they won't impress me, not to speak about a lady).
You can be sure that, after she knows that she means more to you than some computer games, that having a good time means she and you have a good time (not you ONLY), she will want you enough. Until those days (more than one evening, I mean), you can have all the fun you want (alone).