How did you manage cot to bed with child who doesn't want to go to sleep?

[Lovage]

Sometimes DS (2 yrs) goes to sleep by being put in his cot happily and talking to himself and his toys until he goes to sleep. More often he objects either verbally or by crying. He tries to climb out (he can't yet) and cries for up to 2 minutes. Then he stops crying and either goes to sleep straightaway (naptime) or talks happily to himself and his toys for about an hour then goes to sleep (bedtime). So this all works okay (although obviously I'd rather he didn't cry at all, but I can cope with 2 mins). But it completely depends on him not being able to get out of bed in the initial few minutes.

How on earth is this going to work once he's in a bed? Need the cot for new baby in Oct and anyway he can nearly climb out. If we stay in the room with him he doesn't go to sleep at all. Any experiences with children with a similar pattern? Or children who seem to need to cry for a longer period before going to sleep?