Custom Lubuntu iso errors

view story

http://askubuntu.com – I am working on a project for which I need to make a specific and lightweight linux distribution. I have made a custom LiveCD ISO based on Lubuntu 12.04 for my project, and when I try running it in Virtualbox 4.2.6 it starts all right and gives the boot options menu (See figure 1). However, when I check the disk for defects, it says there is one (see figures 2 and 3). I NEED TO KNOW EXACTLY WHICH FILE THE PROBLEM IS IN It also will not start the livecd system or installer, supposedly for some sort of BIOS problem (see figure 4). Please someone help. I have a deadline on this project. Twtduck.i (HowTos)