1. Go and see that movie. I promise you it's worth your while.
2. Go and see that movie. I promise you it's worth it.
Do sentence 1 and sentence 2 have the same meaning?
They do mean the same thing, though I would always use "worth your while" in the future tense. "I promise you it WILL BE worth your while."
Sentence 2 is fine in the present tense.