Lubuntu DVD does not boot

view full story

http://askubuntu.com – I downloaded from Lubuntu ISO from the first link on the lubuntu website. Burned a DVD with CD Burner XP in another PC , and at the target computer changed BIOS boot settings to boot from CD/DVD drive first. Now at the target computer there was an old Ubuntu 8,04 Hardy Heron already installed. The DVD does not get detected when i put newly burned DVD at DVD drive. Where am I wrong? Is there something that I misunderstood, for example, Lubuntu is really an OS which can be installed on Hard Disk? (HowTos)