Can people connect to me if Limewire is not active?

[darogo]

hi,
whenever i launch limewire and check the "connections" tab, i see there are many hosts connected to my computer. even if i turn off file sharing, i still see ip addresses connected to me for what seems to be a long period of time if i'm not sharing any files.
if my computer is on and my dsl active but WITHOUT limewire open, can people still connect to me? if filesharing is off, is there anything i need to worry about?
i'm a bit worried about having an open port authorized for Limewire. can't someone just hack into my computer thru that open port?

thanks a lot.