Did you install Ubuntu using Wubi by any chance? That could be part of the problem
Alternately, it could be that you need to reinstall the bootloader.
Try this tutorial:
http://ubuntuguide.net/how-to-restor...ws-xpvistawin7
Just a sidenote, it's Ubuntu 9.10, not 9.1, the last two digits are the month it was released in (ie 9.10 is October of 2009, 8.04 is April of 2008, etc.)