I've owned both leopard and crested geckos, and I'd say it really depends on what works best for you, and the personality of the gecko. I have a docile crested gecko and a skittish leopard gecko, but I've heard it's the other way around for a lot of people.
Leopard gecko pros: Lots of personality, only eat every few days, rarely drop tails, and less jumpy.
Leopard gecko cons: Require heat, and more difficult to remove stuck shed.
Crested gecko pros: Easy to handle and don't require heat (depending on environment.)
Crested gecko cons: Jumpy, require daily fruit mix (and occasionally insects,) and some may easily drop their tails.
My first gecko was a leopard gecko, but it completely depends on your preference. When you're able to, go out to your local reptile shop/show and handle a few geckos, then go from there. Good luck!