network boot/ reinstall problems

Archived from groups: microsoft.public.windowsxp.hardware (More info?)

i am running xp home on my laptop. i don't have an
internal cdrom drive, only an external (usb) one. i want
to format my hdd, but without a cdrom drive, i'm having
difficulties. 1) how do i boot over a network? i have
another computer (also xp home) that i can network to,
but i don't know how to boot it properly. 2) can one
boot a usb device? i checked bios, and the usb drive is
not listed, but can i change anything so that it will
read the usb and boot from the external drive?

thanks in advance,

tim