In addition to Mat Alan's excellent advise, when you have your new disc, check it for defects. In fact you can check the one you've got!
When the disc first starts to boot, press any key (I find the space bar works well). This will give you a boot menu.
Select "Check disc for defects" and let it run until conclusion. You will then get a report as to whether the disc is good or not.
As Mat says, it definitely pays to burn slowly. There are may heavily compressed files on the CD and if just one is corrupt, it can screw up the whole installation process.