boot list has changed

[William Brayden]

I'm running ubuntu 8.10 and just yesterday I re booted to exit 
ubuntu/Linux to boot to windows XP and found that the option to select 
windows XP was gone. The selection only lists the ubuntu versions and 
under other O/S it displays nothing. How do I restore the GRUB to 
include the windows XP option ? my system has 2 hard drives one for 
ubuntu and one for windows. the default boot order is to ubuntu unless I 
select windows in 3 seconds. Can you help me.
William Brayden