I had Dual boot with windows xp and Ubuntu 10.4 on my PC. I have installed Ubuntu 11.10 on the Ubuntu 10.4. After restart it is directly entering into Ubuntu 11.10. There is no menu at start up for selecting Operating system.
Open up a terminal window. Then type:
You'll have to type in your password. This will open up the grub configuration file. Look at the first several lines. You should see something like:
Also, note that
Finally, after making the necessary change, save and exit the editor. At the terminal, as suggested in the grub config file, type
to make the changes stick.