Many guides for changing the default operating system for Grub2 to boot involve setting the number indicating where in the list that OS appears… unfortunately, when kernel updates are released for Ubuntu they shift everything down two places and your default OS therefore changes.
There’s been significant progress made with WebLex in the last few weeks. Mainly through avoidance of revision… Anyway, there is now a beta version out for both Ubuntu and Windows. These can be found at http://www.weblex.org/
The latest version is written in Python and will hopefully be coming to Apple’s OS X shortly too. French and Spanish support are still extremely limited, but this will be improved over time.