Do a speed test (with only your browser open)
http://www.dslreports.com/speedtest?more=1

These couple of posts below explain a bit about speeds & should help you to set your speed in LW. You can change your speed by going to tools > options > speed. Click Apply & Ok to save any changes. No need to reinstall

http://www.gnutellaforums.com/showpo...34&postcount=5
http://www.gnutellaforums.com/showpo...24&postcount=6

There's some good info in the thread below, about setting up your LW for best performance. Check out the first few posts by murasame.
Configuring LW for best performance