Putting mac to sleep will cut stop everything. ie: no cpu or ram or hdd or network activity.

File menu > connect/disconnect is for connecting or disconnecting from the gnutella network. My OSX LW is set for auto connect when I start the program. But in OS 9, I have that LW set for manual connect so I open LW & let it load shared files & incompletes, then after it's settled I use the connect option from file menu.

For your original question about no. # of shared files, if you are allowing partial file sharing then files you are presently downlding will also be shared. This helps the network. So people can download chunks of a file you have already downlded & get the rest from others. But this doesn't normally show as a no. # in the shared files total.
However, it's my guess the most probable reason is you are sharing a windows update file. This is stored in your LW prefs folder. There's normally 3 of them. This helps windows people who are installing/updating LW to get it faster.