If I install a copy of Windows Xp on one machine, can I use the same disc on another machine?

the above isn't entirely true, I reinstalled my uncles windows with my CD. So it should work.

yes it's very simple.... but ur use came configure system... and use gost software.. search and download Ghost software...

No you don't need another license since u r transferring the same license to another machine. However there is a catch here. If you removed your Hard Disk from the old PC and put it in a new PC and boot, it will detect the hardware change and ask for re-validation of XP. At that time you may face problems registering the XP since its already registered with the OLD PC. In such a scenario call the toll free microsoft support number and explain the situation to them and they will give u the new activation number after verifying your purchase details. And now you are through.

I the CD copy of the XP is the original and it has multiple licence you should have no problem. However, Microsoft is become wiser this days, if you install the XP with a single licence on another computer, you may need to connect on the internet to activate your licenced software or you may have to some numbers from the dealer you bought the software from.... And finally, if you are installing a single licence software, you my have to purchase another licence which will enable you to activiate the software, in such a case you are not buying, the CD but rather the licence for the software on the computer.