Anirbandd,Whichever Ubuntu you install(I installed 12.10),make sure to uninstall it carefully if you don't like it and replace the boot loader (I think that is what it is called
) with a repaired master boot record before booting into windows,else windows won't boot.I made that mistake and had to format my HDD as the MBR did not fix itself with the commands given.And why not try it from a USB Drive if your DVD is not working.I did it from a bootable USB stick created using Universal USB installer--
Universal USB Installer – Easy as 1 2 3 | USB Pen Drive Linux
Instructions--
How to create a bootable USB stick on Windows | Ubuntu
And to bring up the boot menu,you have to repeatedly press F12 on some computers,as written here--
Install Ubuntu 12.10 | Ubuntu
And yes,happy birthday ! And best of luck installing ubuntu....