In Bg2, it says that "your adventure doesnt have to end when you beath the game, you can import your character to neverwinter nights" is it true? I can import my character to NWN? (I'm sure that he'll be level 1 but what about the stats? Will they stay the same, if yes it's nice!!!)

Sadly, no. Bioware admitted on their forums to being overly optimistic back when they added that note in bg2, but the sheer difficulty/impossibility of tranlating 2nd ed. to 3rd ed. made character importing get the axe.