Dropped - high or low percentage ?? & browsing users

I tried limewire today and for the first time i got search results. I'm connected to many hosts, still i don't find the files I want and get less results then i would get for the same search query in other file sharing programs. I guess it would get better if i would manage the hosts I'm connected to, but i don't really know how.

My problem is:
I don't know what the "dropped (I/O)" column in the connection tab means. Should I try to have hosts with a HIGH percentage or low (0%). I.e: one is 51/100 and the second one 2/0 . what does that mean, which one should i remove?
thank you very much!

And could anyone explain the communities thing to me? I connect to one, but it doesn't seem to have any effect i.e i connect to audio and may also get video results..

Oh, and browsing other users NEVER work, maybe because of my firewall?

Thank you for your help!