installation problem

[Francesco B]

Hello!
   I am completely new to this list and to Ubuntu and hope that I can get some assistance. 
   I wish to migrate from Vista (uuuugh!) to Linux and I received the installation disc for Ubuntu 8.04.1. I followed the instructions to install it inside Windows and rebooted. I chose to boot with Ubuntu. The screen with the Ubuntu logo appeared, but at this point the progress bar kept running without results. After a couple of minutes the pc restarted. 
   Attempts to boot with the Ubuntu CD in the drive are completely ignored.
Any suggestion?
   My hardware: Dell Inspiron 530 with 4GB RAM and 500 GB Disk.
   Thank you in advance for any help!
Sincerely

Francesco
UK