The first one, without question, would be GTA. It's been the same glitch-laden fest since GTA3, just with a different city design. Give me a chance to kill off another, and it'd be tough, since I'd be looking over at those yearly EA Sports games... or maybe I'll just kill off Metal Gear. It seems as though Solid is now being sold out to whoever will pay a buck for it.

Ratchet and Clank

What are they up to now 7? 8?

this.

Mario....he needs to be buried and let some new nintendo IP take over.

Guitar Hero, Rock Band, Pokemon, CoD, Mario, Zelda, Halo, Dynasty Warriors, Tony Hawk games....sorry just couldn't stop :P

The Shaq-Fu franchise.

Kingdom of Hearts just to see Soriku suffer...I'm still mad at his SoA comment and as a SEGA fanboy I must make him suffer!

Ratchet and Clank should end, let Insomniac start on a new platforming franchise, Ratchet is getting tired

Crash Bandicoot should have stopped after Crash Bash (I know it was not ND, but it was great fun)

halo

after ODST i was hoping it was done, atleast for awhile. but nope here comes :reach. it needs to take a break after that.

When answering this question, you have to ask yourself this
1. What series is not enjoyable to play
2. What series is declining in sales, scores, and fanbase

Based on this...Sonic is the series that needs to end. No offense Sonic.