Not intending to steal anyone's thunder but, the green link in my signature does this.
I change the picture and the font colors once in a while. Other than that it never has to be touched unless you install or delete an OS.
Here is a picture of my current Grub2 screen in Raring:
20130529_110744.jpg
You pretty much just have to point each entry to the correct partition e.g. sda2 for each OS.
Code:
cavsfan@cavsfan-MS-7529:~$ grep -e "menuentry " -e "submenu" /boot/grub/grub.cfg | sed 's/^[ \t]*//' | cut -d "'" -f1,2 | nl --starting-line-number=0
0 menuentry "Precise Pangolin 12.04" {
1 menuentry "Precise Pangolin 12.04 (Recovery Mode)" {
2 menuentry "Quantal Quetzal 12.10" {
3 menuentry "Quantal Quetzal 12.10 (Recovery Mode)" {
4 menuentry "Raring Ringtail 13.04" {
5 menuentry "Raring Ringtail 13.04 (Recovery Mode)" {
6 menuentry "Saucy Salamander 13.10" {
7 menuentry "Saucy Salamander 13.10 (Recovery Mode)" {
8 menuentry "Linux Mint 14 Nadia" {
9 menuentry "Linux Mint 14 Nadia (Recovery Mode)" {
10 menuentry "Windows 7" {