When I installed Win2k I named the computer "Andy" but now I want to call it something more meaningful. Are there any hidden catches or problems if you change your computer name? For example, I note that profiles have names such as Andy\User1 - how will these be affected? Will file permission be affected etc? Thanks for any advice/reassurance.

If you are a member of a domain, you will have to disjoin and rejoin the domain. If not that step won't be necessary. Permissions should not be affected, and a new profile will be added with the new name. If you want to keep your settings, just copy the contents of the old profile into the newly created profile.