That tank is an odd size, but i would find that a nice Amazon Tree boa would be perfect in there. They can be had for around $150, which is cheap for Arboreal Snakes. If it were Lizards, i would take a good look at Day Geckos. Bright green, Diurnal and very easy to care for. They are very fast, so not too handle able, but a very good display animal.
Crested Geckos would love that tank, but you have to worry about dominance and aggression issues as they get older. They are literally the EASIEST animal to take care of. No heat, no light, no live food needed. What else could you ask for?
125 Gallon Dirted/Fully Planted Community Tank
55 Gallon Amazon Tiger Barb Tank
29 Gallon CRS Shrimp Tank
20 Gallon Yellow Neo Tank
20 Gallon Half Moon Amazon Serpea Tank.
10 Gallon Blue Velvet Neo's
10 Gallon Betta/Cherry Neo Tank
10 Gallon Betta Tank
12G Rimless Club