[ubuntu] Installation woes

I am trying to install Ubuntu 13.04 - I have tried countless times (32- and 64-bit versions) to install. It loads initially and then I get 'unable to find a medium containing a live file system'. I have followed the correct installation process, and still no luck.

I am trying to install it on an AMD 64-bit system with 2.5Gb memory.

There doesn't seem to be the required files on the DVD. Here's a list:

Folders


.disk
boot
casper
dists
EFI
install
isolinux
pics
pool
preseed

Files

autorun.inf
md5sum.txt
README.diskdefines
wubi.exe

Any ideas please?