minecraft-seeds.net/.../All-Seeds is a good place to check out, i think all the seeds under beta 1.3 - 1.7.3 should work with xbox, worstseedever and a few other known seeds are among
the list, but i'm fine with 'wse' so i haven't done much world hoping.
try "ZOBOBRICK" ...mostly forrest, about 1/5 desert...no snow though, lots of cool terrain features, and at least 8 massive caves open to the surface within view range of the spawn...I havn't gotten around to exploring the caves much yet, because I've been
busy flattening a huge area around the spawn and building a town on it....I'm loving it so far...oh!...and hundreds of red mushrooms! :D
Try the map with the seed of brick All lower case. There is a ton of clay in it. As well, it is by far the best map for terrain I have found. I am starting new on it this week but a friend had it for a while. It has mountains or these crazy
undercut formations that reach in to the clouds. I went to the top of one built up 12 bricks and was at the top of the world literally couldn't go higher. The clouds go through the top of the hills. The mountains are to the west from then center of the seed.
I guess there are other awesome formations around though too.
Try the seed Joshua capitalized j, you spawn on a pretty large stone biome and there is a large overhang bridge really close to it. But the best part is htere is a cave that goes straight down to at least lvl 24 when your on 79. Try it