If you have installed Windows in your computer first,commonly windows will be in grub menu after you install ubuntu.But there’s always someone can’t boot windows after install ubuntu.In this tutorial I’ll tell how to figure out it.
First,boot up your ubuntu and open up a terminal window,edit menu.lis file by following command
sudo gedit /boot/grub/menu.lst
Add following section in the screen
title Microsoft Windows, Codename: XP root (hd0,0) savedefault makeactive chainloader +1
Here root (hd0,0), means my windows was installed in the first partition of first hard disk.
Click here,if you want to make windows boot up as default OS.