Ultrapeers (UP) help other people (Leafs) connect to the network. It only uses a small % of your bandwidth (upload), but is just as valuable to the network as uploaders are. The network itself decides if it needs more UPs & if it does in your local region, & you are are not firewalled & have sufficient bandwidth, you may become a UP.

There is no option to become a UP. It is decided for you. However, there is an option to disable it in LW's Options settings.

LW Pro connects to 5 UP's, whereas Basic connects to 3. The extra UP's are most helpful for searching rarer files by reaching a wider audience. Also with Pro you can download from up to 10 hosts per file compared to Basic's 8. That is why it is potentially faster than LW Basic.

Turbo connection is not restricted to Pro. But Pro will almost always be turbo charged, whereas Basic will find it more difficult to get to that status. For many people it rarely does.