Change default boot option in multy-OS systems

Assuming that you have Grub boot loader (common in most of the Linux Distros.)
To change ur default boot option, do as follows:
Open terminal, then type the following codes(don't type $ or #, it will appear by itself)
$ su
enter ur admin password..
# cd /boot/grub 
(you will enter in to grub directory, there is a file named grub.conf. You have to edit it in some editor like Vim or Gedit, im going to use gedit. so type the following).
# gedit grub.conf 
gedit window will show u details something like below.

default=0
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz
title Fedora Core details......
........................
..........................
title Windows details......
........................
..........................
You can see the first line having default as 0 means the first OS (see title) is default. If default is 1, second title. If default is 2 third tiltle would be the default OS to get booted.
So just choose default as 1 in ur windows is in second position.
save the current changes and reboot.