How Do I Delete Windows

I recently downloaded windows xp home edition ,
I have windows xp professional and windows 98 on it .
I only want to run windows xp home edition how can I get rid of the other two ? every time I start my computer it asks me which system would i like to log into ... please help me delete windows xp professional and windows 98 !
Its taking up all my drive and making my computer very slow

 

Under rare circumstances, you may need to uninstall Windows XP Professional and return to your original operating system.

To uninstall Windows XP

• Click Start, click Control Panel, click Add or Remove Programs.

• Click Windows XP Professional, click Remove and then follow the instructions on your screen.

IMPORTANT
You cannot uninstall Windows XP Professional if you:

• Changed your hard disk configuration, for example, if you have converted from FAT to NTFS or have created partitions

• Upgraded from Windows NT 4.0 or Windows 2000 Professional.


This site is for uninstalling Windows 98

http://support.microsoft.com/default.aspx?scid=kb;EN-US;186102