It is possible to boot from a dvd...look arround, there are many sites dedicated to slipstreaming stuff into the XP install cd and how to make bootable cd's (the same applies to dvd's)
Or are you asking if you can install XP with a dvd drive, yes you can, because all (correct me if wrong) dvd drives can read cd's (if they have the Compact Disc logo on them)
I have personally installed Windows XP Professional from DVD-ROMs many times. The disk was an original Microsoft distribution disk, and the readers were a smattering of Toshiba, LiteON, and Sony drives. No issues whatsoever.
It's my understanding that DVD-ROMs should read CD's transparantly; that is, it's just data to the operating system - no difference.
k, just makin sure... cause I know in the old days the DVD-ROMs needed drivers to function and therefor couldn't be used to install the OS... anyways... thanks guys