Definitely go with Mushrooms and Polyps (Zoanthids) as Lynden mentioned. They are VERY forgiving and quite hardy. Not to mention attractive...then you can maybe move on to Ricordea and Palythoa. It's pretty simple all in all...
Live Rock = Rocks that are alive with bacteria.
Corals = Generally just as sensitive as fish so be just as careful with both.
Patience = Most important virtue in this world.
Add your water, add your salt, adjust specific gravity via hydrometer, adjust pH via buffer, adjust temperature via heater/chiller, maintain stable SG, pH, and Temp. Add rocks, add sand, wait for ammonia, nitrite, nitrate to reach zero via test kits, add clean up crew (hermits, snails, etc.), add fish, add corals. Tada, reef
Sounds easy, huh?