[ubuntu] Can't install 13.10 by optical disc drive even though disc drive is fine

Hello folks,

I am a newbie Ubuntu user. I want to upgrade my version to Ubuntu 13.10 by making a fresh install. I downloaded the ISO image of 64 bit version of Ubuntu 13.10 and burned it on a DVD. I also checked the image by doing checksum. The optical disc drive is working fine as it mounts other CD and DVDs. But when I try to install Ubuntu 13.10 by using live DVD then I can only see the contents of DVD after my version(13.04) of Ubuntu loads. The menu to try Ubuntu or install Ubuntu does not show up when I restart my HP desktop. It just logs in to my account and loads Ubuntu 13.04. To say it simply, I can't do a fresh install of Ubuntu 13.10 because the menu to install it does not show up during start up.

Would you kindly enlighten me to install 13.10 by a live DVD. I've burned three DVDs of 13.10 and checked all of them but still I can't use those DVDs to install 13.10.


Thank you very much in advance.