I'm afraid most of my responses would not be etiquettely approved.
Sticking with appropriate responses, may I suggest:
1. Don't take it. Keep your hands in your pockets or put them behind your back when he tries to hand you the DVD. Repeat "No, we don't want it."
2. So he sticks it in your purse/pocket anyway. Take it out and drop it on the ground or toss it in the nearest trash can, preferably while he's watching.
3. This is my father's approach: Tell him, "I'll give you equal time. I'll listen quietly to you for 10 minutes, but you have to listen to us - quietly and without interrupting - for 10 minutes." If he is a friend you wish to keep, this might be better than throwing the DVD in the garbage.
I've gotten to the point where I refuse to discuss politics with my family, and I love them. When they "go there," I say, "I'm going to ring off if you keep harping on XYZ." They have a choice, drop it or talk to someone else. Friends of family - forgetaboutit! You are not going to persuade me. You are just going to irritate me. If you want to irritate me, then you are clearly not my friend. End of conversation and, hopefully, end of relationship. I have enough toxic people in my life. One less would be an improvement. Life is too short.
Whatever you do, don't engage. You don't have to say anything. Your actions make it clear that you are not interested in hearing his political opinions. If he says, "Oh you Grapes ..." turn your back on him and walk away while he is speaking.