Help! Project on Getting Windows OS onto a bootable USB external HD..

[integlspwr]

I was tasked at work to imaging software CD and put them on a 2-3TB External USB Hard Drive..

The software cd's are farily easy to do but I'm stuck on the Windows OS CDs. We have XP, Vista, Windows 7 etc....

What I need to do is be able to make bootable images of each of the Windows OS cds/dvds on to the External USB Drive.

I have a Mac Pro Tower Running Lion.

Any help is greatly appreciated.

Thanks!