Installation problem

When I try to install Ubuntu 9.04 in my Asus Z53J laptop it gives me a lot of problems.

First, it does't let me boot it from a CD, so I boot it from a USB drive and it works fine as a Live CD. But, when I try to install it it gives me multiple errors. I have already check for errors in the download and burn of the CD and USB drive, and, every time I check, it gives me the correct code for the dm5 (or something like that) file.

These errors occur after I have aswered all the questions about the installation (selected the time zone, name of the user, password, etc) and i press "Install". Everything appears to be fine but an error window pops out when it reaches the 15% of the first partition installation. The window says:
 " Error!!!
Input/output error during read on /dev/sda
Retry Ignore Cancel"

It says it like 5 times, if I press "ignore," and I could stay the whole day pressing "retry" 'cause the window pops again and again. If I press "cancel," it exits from the installation. After pressing "ignore" a few times, the installation window changes to load the second partition, and then it says that it is unable to install the second partition and it exits from the installation.

This happens using all the default settings, I'm afraid of changing anything anf finally breaking my computer.
What is the problem? Can I fix it?

Tank you