yes it is. i used windows 98 before and it is so slow and crazy.
No
Yes. If you insert your Windows XP CD while Windows 98 is running, it will ask you if you'd like to upgrade. It will then copy some basic files to the hard drive and restart.
Yes, it is possible to upgrade from Windows 98 to Windows XP. IF your hardware is good enough. Source: http://support.microsoft.com/kb/316941
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