Win98 + Win2000 = ?

Is it possible to install Windows 98 on C:\Windows and Windows 2000 on C:\WinNT ( and not on D:) without sharing the directory Program Files ?
I know I can install them on different partitions but I would prefer this solution if it doesn’t mess thesystem!
Moreover, whatever the solution I choose, if I instal Win98 first and Win2000 after, will a menu be created automatically at the boot ?

Thanks.

“And so it begins…” (Kosh, Babylon5)