As you probably know, Moab is famous for mountain biking and has some of the best trails in the world. Whether you are a beginner up to a pro, the Moab area has trails everyone can enjoy. I suggest the Moab Brand trails (Bar M area) for one. There's everything from green to black there. The Navajo Rocks area also has some good options. Both of those areas have different loops and ways to ride them. If you want to escape the heat in the Summer, the La Sal Mountains have some great high elevation trails and it's much cooler up there. One favorite starts high in the La Sals and ends up in Moab. It's mostly a downhill (shuttle ride), but it's a long ride and not for beginners. It's called The Whole Enchilada. Slickrock is always a classic fun one to do, but it's also not a beginner trail. If you want a fun loop with some good technical riding, go up Hymasa and down Captain Ahab. Ahab is a downhill only trail and it's fast, technical and amazing. Whatever you ride, be sure and bring plenty of water and energy bars, etc. Utahmountainbiking.com has some great information on specific trails in the area. Trailforks.com also has the trails with maps.