1) choosing linux as O/S from boot
may I suggest editing the grub "menu.lst", making your linux the default system?
load into your live OS and edit the file /boot/grub/menu.lst
...this way you will not need a keyboard to choose linux from grub menu.
the official grub page is at www gnu org
2) keyboard not recognized by BIOS
can you borrow or otherwise acquire a ps2 keyboard for getting into BIOS?
(fyi> www dot SYSOPT dot com : thread 188809: Subject: USB Keyboard Problem)
Indeed, non-ps/2 keyboard can be a nightmare to use, I myself have switched back to ps2 after similar issues.
----------------------------------------------------
wishing you a speedy resolution