Ubuntu has a very user-friendly installation interface. The whole installation takes only a few mouse-clicks and takes only around 15-20 minutes on almost any new system. We have not had any complications in Ubuntu Installations until recently when we had to Install Ubuntu on an Intel 945GCNL motherboard with Intel Dual Core processor.
The installer normally detects other operating systems that are already installed on the computer and adds them to the boot menu. GRUB is the default boot loader and by default it is installed on to the MBR. After installation of Ubuntu on this specific system when the computer restarted we got the dreaded "DISK BOOT FAILURE, INSERT SYSTEM DISKA ND PRESS ENTER" error.
We were however able to boot of the Ubuntu CD from which we could select the boot off the first hard disk option and then boot off the first hard disk. Initially we thought it was an MBR error caused during the grub installation and we reinstalled grub. The disk still failed to boot. We had earlier some boot problems from a SATA hard drive and we checked the detailed boot messages and there was no clue.
After little Google Searching pointed towards a problem with Intel motherboards which caused them to check for the bootable flag on the partitions to check for valid system disks. The bootable flag was ON on the Linux partition. However the Linux partition was a secondary partition as we had left a few empty FAT32 partitions as primary partitions. We then set the bootable flag on an empty FAT32 partition and presto the system started booting just fine.