Brad and Angelina would be my choice. It appears to me that they know it's NOT all about them. Because of that that they have more to offer children. Their love would be freely given and would have no strings attached. They'd have children because they wanted them--not because it looks good in the press. Sure, she seems a little odd, but I can't help admire her. I think a child could learn a lot of positive things from these two.
Brittney is too young and is in an unstable relationship.
Tom Cruise can't see too far past himself. Just listen to him talk--me, me, me, me, me, Katie. It makes me sick to listen to him--and I used to be a fan! And, who's Katie? She's next to invisible in this whole thing. And, I worry about her parenting skills. Who leaves a three week old home while you go dancing at a fancy party? She'll do whatever he says. I cannot imagine the problems their little Suri will have in the future.
Madonna--well, she's Madonna. I don't think she's a good role model for anyone! Just because you write a couple of children's books doesn't make you an effective parent. Somehow, I imagine her children spending most of their time with a Nanny while she pursues her interests--religion, writing books, touring, movies, etc. I'm not sure how hands-on she really is--unless there are papparazzi around. THEN, she's the doting mother.