how to installboth dos and xp

First install DOS. When installed an bootable, install WinXP from the bootable CD drive. If you will install DOS and WinXP at the same partition, you have to use a FAT32 partition and MS-DOS 7, to manage that. Otherwise, you have to use a seperate partiions for DOS. When installing WinXP, it normally recognizes, that there is also a bootable DOS and creates an entry in the Bootmenu of Windows XP. After that, you have the choice on what to start. Please send a reply, if you solved the problem !!!

I suggest you choose to run DOS inside a virtual machine as MS Virtual PC or open source VirtualBox (both are free), avoiding the dual boot set up. In that way you can run both environments concurrently and with no risk to damage the master boot record.