Comment 21 for bug 107259

I was hoping you'd get a breakthrough. You can switch whether Ubuntu or Windows comes up as default by doing Applications, Accessories, Terminal
sudo gedit /boot/grub/menu.lst (where l is lower case L)
Look for the groups of entries starting with "title". The default will be the first entry, so I habitually switch the intact groups around as needed.
This is a critical file used in boot, so you may wish to make a backup before editing.
Cheers, Jerry