I would suggest skipping Chameleons as a beginner.
I second that fire-bellied toads and newts are an excellent option for the setup as you're describing it. They do well in cooler temperatures, they will use both aquatic and terrestrial sections in a paludarium, and they're not particularly demanding.
For plants, you can use a diversity of species, depending on the saturation of your substrate, the prevalence of dry areas and micro-climates, and their delicacy relative to the weight of the intended inhabitants. For the background and branches, vining species of Pepperomia
, and possibly Hoya
are excellent candidates. Examples include P. prostrata, P. rotundifolia, F. pumilo, F. quercifolia,
and H. curtisii
. You can also intersperse epiphytic plants including miniature orchids (a little more advanced,) bromeliads (Neoregelia
are a good option,) and Tillandsia. For larger-leaved or background plants, Begonias, some Aroids, and Korean rock ferns are all options. For the foreground, you might consider leaf litter (just dead, sterilized leaves that allow hiding places for inhabitants,) Hemianthus callitrichoides
, or various species of aquatic moss or liverwort (Christmas, Java, Taiwan moss, etc. and Riccia fluitans
.) You can also try terrestrial mosses like sphagnum and pillow moss, though these tend to be hit-or-miss. There are quite a few valid options, but all the ones I mentioned are pretty easy if you read up on their care.
Mold tends to flare up within the first few months of introducing a piece of wood to a vivarium, but it soon dies off in most cases. You can manage it more easily if you introduce a clean-up crew of springtails and isopods. These also provide active foraging opportunities for the tank's carnivorous inhabitants. On a similar subject, you could introduce small aquatic snails and potentially a few shrimp to your water section, but these may very likely be eaten. I would not generally suggest fish as both the fish and the amphibians will likely be a little stressed by the presence of the other.
As for other inhabitants, I would not generally suggest mixing species of amphibians or reptiles. Generally, this leads to higher stress for the inhabitants of the vivarium and the potential for novel pathogens.
Here are a couple of really attractive setups that may inspire you or provide a guideline:
FlyingSquirrel's Paludarium (different site) :
Good luck with your build!