I would be expecting Internet Explorer D/L speeds of 55-64 K/s
( = 64 * 8 = 512 *1024 baud )
Do not alter your MTU size (this is the packet size that people were talking about. - stands for max. transmission unit ie the number of bytes that TCP will max bucket at one go AFAIR)
As someone else says check your local Ethernet connectivity.
an FTP Xfer should give 1000-1280K from a decent fileserver
Use Ping Plotter (shareware) to monitor hop times.
What are you using to monitor your connection speed anyway ?
where did you get 14KB/s
and note that K = 1024 and not 1000