Help: Computer does not boot initially from CD

[poshan]

I have a P4 computer with 3.06 ghz processor and 512 ddr2 ram. and 80 GB harddisk, 946 GZIS motherboard.
I couldnt detect the cause of the problem. The problem is when I try for new installation of Windows XP from the beginning, my computer does not shows the Press any key to boot from cd.....
So, I cant have a new installation of either XP or Live Linux CDs.
How can I solve this problem? Anyone help me to get out of this.

[praka123]

u might have done this already..but
go to BIOS by press del or f10 and make sure in boot device priority ur DVD/CD drive is set as first device.