This may be a bit of a silly question but i never really understood why Roth wanted Mike out in GF2. I kind of thought that since Roth was based loosely on Meyer Lansky, that he must have viewed Mike the same way that Lansky viewed Anastasia and wanted Cuba all to himself. What do you guys think?

I believe it all ties into the duplicity and double crossing between Roth & Michael. Both tried to keep the other chasing the proverbial carrot to each other's face, then tried to work like crazy to overtake the other behind the scenes. Michael answers your question at the meeting among Hagen, Rocco & Neri toward the end of the film: "He's been dying of the same heart attack for twenty years." It's also answered in Fredo & Mike's discussion: "It was ROTH all along. He acts like I'm his son -- his successor -- but he thinks he's gonna live forever -- and he wants me out."

Roth wanted to lure Michael to Havanna to get his $2 million for their "partnership." When Roth received the $2 million, he tried to kill Michael. Michael was equally adept at hiding his intentions: he had Fredo bring the $2 million to Havana but kept on stalling Roth. With Roth out of the way, Michael would have control over much of Roth's empire.

Why would Wal-Mart want K-Mart out? Why would Shell want Exxon out? Money, control, profit, self-aggrandizement. The list goes on.

Yeah good points I also thought the revenge factor might be a little at play here. Roth was supposedly close with Moe Greene and perhaps knew that Mike had killed him

Roth wanted Michael out because Michael was trying to force Roth out:
Roth and Vito were partners, but only in the Prohibition booze business, not in gambling--Vito owned New York, Roth owned Nevada and Havana. But Michael was greedy for Roth's holdings. The first deal we see him in after his return from Sicily is to try to force Moe Green out of his hotel and, when Moe resisted, to kill him. By the opening of GFII (late '58) Michael has moved his entire operation to Nevada, owns or controls three hotels, and is making a move on the fourth. He also has designs on Roth's Havana gaming empire. Small wonder Roth felt threatened.

The Roth-Michael chess game in GF II is one of the best parts of the movie. Roth lures Michael by "allowing" him to move Klingman out, but thinking all along that eventually he will get it all back.

I always like that hotel room scene where a half-naked Roth tells Michael "I'm bigger than US Steel."

I wonder what Mrs. Roth had to say about that.

"Yes you are honey. But then again, I'm a big girl ... everywhere."

I thought that was Lucy Mancini

She had Sonny to plug the gap.