Is it possible to create a boot cd that will then divert to run an operating system etc from a USB hard drive?

I want to use some hardware, but to bypass the current harddrive as it has policy I cannot interfere with?

Any ideas any experts?

Have been told can just swap and put in new harddrive but sounds a little trouble to keep swapping, wear in connections etc.

 

id just swap them mate less trouble

 

why swap them most mother board have 2 ide's just buy another hard drive, in the bios set the computer to boot from what ever hard drive you want to use