Halo... kinda. The only reason I want Halo on 360 is so they finish the damn story. Halo 2 was like sex without orgasm... decently pleasing until the lack of a big finish. But beyond Halo 3, Halo needs to die a noble death.
I'd like to see FIFA die off... and be replaced with Winning Eleven. FIFA2005 has nothing on WE8 except EA's PR muscle.
Mascot games in general. Chronic the Hemp-hog, Crash Bandaid-cooch, etc... I'm tired of companies trying to make cute fuzzy animals have badass attitudes just to give a system an icon for little kids to identify with.
$20 games. If a company can't put its heart and soul into a game, then they shouldn't be making one. I won't buy a game that's less than $40 because I'm *afraid* of what's not worth the $20 inside. Unless it's a platinum collection, make the game WORTH $40 or more.
GTA-style Crime games. If it's not a MMOG leave it at the door. GTA's been done to death. Mission games are fine, but when it becomes a challenge to keep your character thin... it's time to die. I want to go up against human competitors in a turf match.
Unfortunatly, you'll never get rid of sports games that have yearly updates... there are just too many people who will pay $50 for an updated roster. What I think they should do is make the game $60 and send roster updates via content download; then they can save the REAL game/engine upgrades for a NEW game every 2 years.
Mortal Kombat. I really loved Deception despite it's awful (compared to DOA) gameplay. However, I think we need to say goodbye to this game and its 7 (

) or more iterations. A new fighting game with fatalities would be fun, just not with the words Mortal and Kombat in the title.
Dead to Rights... they haven't gotten it right yet, they aren't going to. Max Payne has a better story anyway.
WWII games in general. I swear there were no less than 4 WWII FPS games at E3 this year. Why? How many ways can you fight the same 4 year battle?? It's history, leave it there... for at least a few years.
Games based on movies. I saw the movie... I don't want to play it. Chances are developers butchered the content anyway. Constantine? Fantastic 4? Riddick? All terrible in my book. Spiderman 2 was the only exception to this.
Hmm, I'm sure I'll think of more later.