Long story short, nope. There isn't.
There doesn't seem to be a way to enable them within multiplayer. It kind of makes sense though. In single player, the popups and movies all fall into the same category (single player help).
If you were able to enable it within the multiplayer game, imagine how much longer the game would take (say a movie is about 10 seconds. now let's say you get one every 2 turns, and the game is 200 turns. 10*(200/2) = 1000 seconds or just under 17 minutes. now let's say you actually watched the clips (making them 30 seconds) for half of them. this would put it at roughly 66 minutes. This isn't even including the popups, or if you want to read said popups.
As you can see, it would just hinder the game for everyone else if you had the popups enabled. That being said, there are a number of great resources out there (either in-game, or outside) to help your friend out.
Worse comes to worse, you could talk with your friend (via skype, etc) while you play the game...
Unfortunately for you both, he just won't be able to get the helpful popups while he plays with you online.