what they all said .. it doesn't matter which windows version (98, 98SE, ME, NT, 2000, xp) you use....
if you are going to share internet connection, it's recommended to get a router to connect all of them... otherwise, one of the machines would have to act as a gateway to connect the other machines to the internet... most of the time, this will require additional NIC, hub, and/or other hardwares..... so it's much easier and efficient to just get a router (shouldn't cost you more than 80$ for a router), plus you don't have to worry about setups and other mess....
if you are going to share files/printers between these computers later, it's easier to share the files between win2k and win2k machines -- of course, it's also possible to go cross windows ... just be sure to read thru
this link to get you started ... also, when connecting from 98/98SE/ME to win2k/NT, be sure to get additional info
here.. the other way (98, etc to win2k) is easy .. you don't even have to do anything...
i'd also recommend going to win2k, because it's more stable, doesn't eat up as much resources (bloated) as xp, and it's easy to get them networked, etc...
good luck
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