New Debian Install - HELP!

[Kitty Litter]

Sounds like grub was installed on your new linux drive but bios is set to 
boot from your windows disk. Many computers you can press f11 several times 
when first starting and you get a menu where you can choose the disk to boot 
from by pressing down-arrow a few times then enter. If you turn the power 
off in the back and turn it on, supposedly these menus are in the same 
sequence. Then whin linux boots you could put grub on the MBR of your 
windows disk if you dare.