Computer reacts toward a normal DVD as a bootable DVD

Hello all,

I have a PC running XP with the following specs. When I put some DVD which contains some apps and multimedia files, and restart the machine, in the boot screen (when the name of the motherboard and other hardware are coming up - the black first screen) it reacts toward that DVD like a bootable DVD and writes "Boot from CD/DVD" and will be frozen. That is, in this case, neither it goes to XP OS nor any other keys (like, Enter, ctrl+alt+del, and so on) work.
I don't know what is the problem with the machine and that DVD.
Is there any idea how to fix this problem please?

Pentium 4 CPU 3 GHz
1 GB RAM
RADEON 9250

Try going into your BIOS and making sure that the DVD drive is not set to the primary boot-up device. The DVD drive only really needs to be the primary boot device when you're installing Windows. Other than that you should set the hard drive to be first boot priority and DVD drive as second.

OK but why the boot is sensitive with this DVD? What do you think please?

Are there boot files on there? Perhaps it was previously used to install Windows?

Does it do it on other computers?

NO.

If it's not a bootable DVD, why are you starting the pc with the disk in ?

an old joke -

patient - 'Doctor, it hurts when I lift my arm like this'
doctor - 'well don't do it'

ie take the disk out before booting

hhhhhh, thanks about the joke. Yes, I know if I don't lift my hand like this that screen will not be frozen! But I like to know the reason. That's all.