The ex's birthday...

So we broke up a few weeks ago. (If you want the whole story go to "...about the ex. woohoo." under the broken hearts forum)

So last week, she called and invited me out to lunch. It went well but this week is her birthday and I am taking her out Thursday evening. I really want her back and I think I am taking the right steps in getting her back. (I know she may not want to but I have to try) I've already told her I agree with the breakup. How should I approach her birthday dinner? Buy her a gift or just take her out? Try to do something after the dinner like watch a movie?