problem on booting my pc

hello,
i have a serious problem. I have installed windows xp professional and i want to format my HD and reinstal Windows. The problem is that i cant boot from cd-rom. At the begin it gives me the prompt: press any key to start from cd-rom. I press enter but nothing happens. It always starts the windows from my hard disk. I selected in bios all boot devices to be cd-rom…. nothing. I made 6 bootable disketes and i tried to use them but worked only the first diskete…. when i had to put the second… drive A: didnt read it and i couldnt either press F3 for escape. The keybord didnt work.
I dont know wat else to do.
Could someone help me, please?
thanks in advance