This looks like an Echeveria that has been kept in a dark spot, hence its leggy look. Its looking for light. Also being a succulent it will not require watering as much,in fact a bit of neglect will not hurt. Move it into a brighter and warmer spot.

By the way, it's the one in the front that I can't recognize :)

The plant at the top edge of the photo looks like it is struggling, too. Is that a Senecio? I'm not sure. Looks like they are all in a bark mulch or compost mix unless that is only a top dressing. The Kalanchoe and Portulacaria seem OK but the other two aren't happy. The soil mix probably needs to be less water retentive for those two plants. That might seem backwards however if a mix is too water retentive then the roots have problems and stop taking up moisture. Then the plant begins to look under watered even when the mix is kept moist.

Looks like Sedum adolphii. It likes full sun so give it as much light as possible, but wean it into the sun or it will burn - just like me! The leaves will turn a reddish brown in sunlight, which is normal. They will also turn a little brown and get soft from too much water, which is a warning sign. To expand on what socks said - it looks like vermiculite on the top of the soil. This will break down and lead to rot. I agree that repotting is a good idea. =)