How to Install Norton Image or Win XP in External Hard disk

Hi…
I am looking for a solution how to install
Win Xp or Norton image into my external hard
disk.. i have put the internal SATA hard drive
in to an external hard disk casing…
But i am not able to install any os or
Norton image into it.. Actually i want
to install win 2003 server in it. can anyone
help in this