Please help me with this...

At work I'm trying to promote linux by installing ubuntu on a computer that's connected to internett, and is mostly used for recreation. I have installed Ubuntu on a separate harddisk, and have NOT installed Grub or LILO on MBR. Not at all actually. I want to use a boot disk for this, so that those who want to try using linux, just need to put in the boot disk before startup. But I just can't figure it out!

Normally they are using WIN2000 witch is installed on a separate harddisk. I unplugged this harddisk when installing Ubuntu. Just to be most safe.

Can some one help me to spread linux to the people

best way would be to use a Ubuntu livecd or livedvd which will automatically boot and wont harm any disks or even offer access to the uninitiated

google for linux bootdisk linux boot floppy or read up on how to use the installation media you used previously to boot into the operating system

If you would have let Ubuntu alter the MBR it would have setup windows and ubuntu in the boot menu

Make a grub boot floppy. You need to make sure that the menu.lst in /boot/grub is pointing to the correct partition and then make the boot floppy. You can can find a fairly detailed guide on one of my pages .