Mojito DHT is for when using Limewire for torrents. If you only use the Gnutella network, then there is no need for it being active.

UltraPeers (UPs) handle the grouping of searches making the network efficient. If you have spare bandwidth then you can be one of them and connect to max. 32 other UPs and 32 leafs (normal users) making your searches a little more effective than the normal 3 or 5 connected UPs will.

TLS I haven't got the faintest idea about. Better let someone else try and answer that one.