problem with LUBUNTU 13.04. on HP PAVILION ze5600 notebook

Hi there, I heard about Lubuntu, and i tried to install it on my HP notebook witch has 512mg of ram, 2.8 Intel CPU and 20GB HDD.
Originally i had a 40gb toshiba drive, and Win XP sp1, but a virus destroyed the drive... So then i replaced it with a 20gb and installed Ubuntu 10.10

I downloaded Lubuntu from the Lubuntu home site . The problem appears when i try to burn the ISO image to a CD. On my hp notebook i tried to burn the iso to a CD with the built in burning program. When i select burning speed, it offers me Max speed and 24x I selected 24x and waited... "Burning complete, some files may be missing"
I know that burning speed must bee minimum (better quality), but now i can't select other then max or 24 :/
Then i transfered the .iso file over my Flash memory to my other laptop and tried to burn it with PowerISO, but same situation (Speed max, or 24x), i also didn't manage to burn the disk properly :P

I used a new CD in both cases. I have used PowerISO before to burn other iso files and i used the same CDs but now it's different and it doesn't work :(
I also tried to use the windows wizard for burning (i don't know what its called ) and a error comes out. Unable to burn CD.

What am i suppose to do in order to solve the problem!?
Thanks (: