Explorer freezes when browsing network shares

Just saw a similar problem posted earlier with no replies, PLEASE HELP...

When browsing shared folders on other computers (all three machines are ME)
Explorer will freeze the whole machine doing the browsing. This happens no
matter what machine is doing the browsing / being browsed, and it happens
EVERY time (after getting 4-5 folders deep or in/out of 4-5 folders).
CTRL-ALT-DEL and ending that Explorer session is the only way out.

** One thing I have noticed is that activity between the machines (watching
the router LEDs) starts out normal, only exchanging data when I open a folder
or file. Suddenly, and for no apparent reason, there is CONSTANT activity
between the two machines and this is when the Explorer session freezes.

I have run every virus scan & ad-ware scan, re-installed ME on all machines,
followed all steps at www.careyholzman.com/net1.htm, and still have this
problem.

ANY HELP WILL BE GREATLY APPRECIATED! Thanks in advance!