Try to avoid trademarks that you don't own; names of people can probably be considered trademarks, if they're famous enough. I suppose it couldn't hurt to try if you can get them cheap, though.
The new gTLDs (actor, flights, etc.) haven't really taken off yet. The more generic ones tend to be the most popular; otherwise, they're typically only good within their respective industries. Even then, they don't seem to have much resale value--yet. At the same time, that could mean they're good investments: they have a lot of room for growth. Don't expect to make a quick buck, though.
At the moment, .com still holds the most value, by far. Personally I like .ninja because I think it's cool, but I'm not expecting to make any money from that TLD anytime soon. I'm willing to bet techies like me will begin to use it quite a bit, though.