You need two copies, although you may qualify for a discount on the second
copy (See URLs below).
If these are proprietary PCs be sure you investigate the upgrade process
thoroughly as it may be difficult or impossible (or easy).

"Windows XP Home Edition is available as a full product or as an upgrade
from Windows 98/Windows 98 SE or Windows Me. Under the Windows XP End-User
License Agreement (EULA), you may install one licensed copy of Windows XP on
one computer."

http://www.microsoft.com/windowsxp/home/howtobuy/pricing.asp
http://www.microsoft.com/windowsxp/home/howtobuy/addlic.asp
*************************************************************
I have not been able to find this info on the web.

What is the difference in the licence/registration process between W98 and
XP Home edition?

Can I install XP on my PC and also install it on my lap top considering
that I never use both of them at the same time?

Or am I really faced with buying an upgrade for both my W98 PC and W98 SE
Laptop?

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