Get both! Neither takes up all that much space and if you breed your own food, they cost next to nothing to maintain.
I'd definately recommend a terrestrial species for a first gecko, although if you love the Golden-taileds, there's no harm going for them.
There are at least four different species of "Bynoe's Geckoes", three of which are sexual (reproduce normally with males and females) and one which is entirely female and reproduces by each female cloning herself. If you want something really nifty, you could go for something which is a clone of a lizard which was around over 100,000 years ago
Here are pictures of some clones
The different species look and behave differently. The Clone Geckoes are quite diurnal. None of them are particularly good handlers, but I have one Clone (one individual) which I've handled every now and again since she hatched, and she handles pretty well.
Nephrurus levis and milii are also great species for beginners.
