I hope you only touches it while you are kissing?
Really awkward and wierd if you just stand/sits there and touches her tits or ass..
But if you have done the touching step without a slap in the face you wont need tips on movie, just put on something decent random from any top-list and kinda cuddle, you'll notice if she is really into the movie or not, if she aint, then take her attention insted of letting her suffer through a shit movie.
Always hard to know in wich way to seduce her while a movie is on without feeling that it will be awkward.
The best tip i can give you is.. find a movie where a guy tries to seduce or kiss a girl and she slaps him, wait to that scene in the movie and seem suprised and ask her if she would slap you if you made a move. You can get 3 answers and 2 of them are good. 1. Yes i would slap you. (dont make a move obv..) 2. No i wont slap you. (ofc kiss her kinda gently and keep it going, not just a poosey kiss) 3. I dont know, find out yourself. ( go ahead she is wet as soon as you touch her)