performance degradation

I love Limewire, but its performance is not so good in terms of download / upload speed. Perhaps I am doing something wrong, or there is a setting I can make to speed things up?

I have a Cable connection, reliable and very fast, but it has never been possible for anyone to download a file from me at a faster speed than about 10 Kb/sec. That's when only 1 or 2 people are downloading. If I let 5 or 10 people simultaneously download, everybody crawls.

Also, even worse, whenever anyone is downloading files, my internet browser crawls at a very very slow speed! I never had these problems with Napster ... can't remember if I've had them with other sharing programs I've tried.

As a result, I never share files anymore when I want to surf, only when I'm away from the computer for a long time. Can someone please make a suggestion? Thanks.