For the land: Bromeliads, ferns, mosses, orchids.
Water surface: duckweed, water spangles, water lettuce, frogbit
Submerged: sword plants, hairgrass, anubias, crypts
Other than the orchids, these are the more beginner plants. They all also have "dwarf" or smaller variations for a tank that size. Keep in mind that surface plants are going to lower the light that is getting to your submerged plants.
Firebelly toads, salamanders, poison dart frogs, turtles, tree frogs, crustaceans. The ideal species is going to depend on your water to land ratio and your experience/commitment/budget. Avoid mixing species unless you have a much larger tank and can focus on an entirely terrestrial and entirely aquatic species. I.E. shrimp and tree frogs.