Try connecting from full management studio, rather than management studio express.
You can install the workstation componenents alone on your client PC from the same DVD that you installed the server.
btw, you may want to patch those servers. SQL 2000 unpatched (testsys 8.0.194) is a massive security risk. SQL 2005 unpatched is a lot better, but there were bugs in the RTM version. Current patch level is SP2.
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