I recently messed up my Master Boot Record and my system is not booting. I was dual booting Windows and Ubuntu. Both of them are not loading now. I don't care if I lose my windows, but I want my Ubuntu back!!
How to get it (I have a fresh Ubuntu 10.10 LTS disk with me). I went through the install wizard but feared that I may loose my existing installation/setup. Thats why I came here to check what is the ideal procedure to only update the Boot record instead of a full installation.
This is covered in detail in the Ubuntu Community Documentation.
If you have an alternate CD you can use "Rescue a broken System" when this has loaded you can see a menu entry to re-install the grub menu.