Can anyone point me in the right direction re installation of a windows operating system.

I can instal XP Home and have a disc but dont have a licence - I know you can get round these but I want to stay legal. On 2 older PC's that have a Windows 98 and Windows 2000 licence code attached, how do i reinstall the O/S?

I can get hold of a 98 O/S and possibly 2000 or ME and have heard about people creating boot discs and I did find a site that allows you to download them but I am still not sure what to do?

Do you just bung in the floppy and CD O/S and tell it to first boot from floppy?

Any help appreciated.

Ash