It all depends.
If, as is usual, your Windows XP install is (quite rightly since it's more stable and secure) on an NTFS formatted hard disk then no. Unless you're prepared to use Partition Magic or similar to create a FAT partition for the DOS games you want to run.
If however your Windows XP install is on a FAT32 partition then I'd use a boot disk. A
great one for gaming is Gameday. Download Gameday.zip from here-
http://jason-n3xt.org/dos/cgi-bin/ikonboard/files.cgi
Put a floppy disk in your drive and extract and run the program. Then, when you want to run a DOS game that you have installed to hard disk, then boot up using the Gameday disk. Switch to your C: drive and then the game's directory and run the game.
Note that you will probably have to set up your sound card's DOS drivers on the gameday disk first.
There are many ways to run recalcitrant DOS games on an XP system. If they won't work in any of the compatibility modes that XP provides then you could even create a seperate partition and install DOS 6.22 or Windows 98 (real name DOS 7.10
).
Boot disks are good though. It may take a bit of work and hit-and-miss attempts to get it right. But it's the best way to learn, eh?
(Note that, if you try Gameday and it can't see your hard disk, then you have the NTFS file system. It's a good file system. But it's not much use for DOS gaming. Consider using a utility to create a small FAT32 partition to use for DOS gaming. Note that this may change your drive letters - particularly the CD-ROM/DVD drive!)
as most of you know 
anybody wanna invest in it?!?!? 
