I'm 6 foot 4 and i weigh 200 pounds, i used to weigh 265.

Right now i am eating 1.2 to 1.5k calories a day. I work out and i lift weights, etc etc. but i've plateaud as some would say.

now everyone is telling me that i need to eat 2.5k calories and stuff. and yeah i know i probably do. but how do i raise my metabolism to 2.5k calories without gaining back any weight?

at this rate what i was hoping to do is get slightly below my goal, then raise my calorie intake and when my body adjusts i'd be at or slightly above my goal.

what can i do?

when you up your calories - you will probably see a change in the scale - doesnt mean you gained fat... just a change in teh scale.
I strongly suggest you spend some time reading the stickied threads...