Drive 1 is your secondary hard drive. It is probably still enabled in BIOS.

There might be other BIOS options. For example, you may have to autodetect the Master Primary hard drive (drive 0) as wells as the Slave drive (drive 1) and it will find none. Go to your Boot Order options and make sure SATA is selected and not the IDE drives. You should be ok after that.

To boot a computer the BIOS must find a boot device. By default, this should be the hard drive that you have windows installed on. The BIOS can't seem to find any of your disks or drives; you seem to have three of them there, so the computer will not boot. When you turn it on, does the CD/DVD drive light up? Can you open the drive? If it can open, open your BIOS and try to find a "Boot Device" section to set the optical drive (your CD/DVD ROM drive) as the main boot device, then put your Windows install disc in and boot from disc. It will give you a message that says "Press any key to boot from disk." From there you can try to repair Windows just in case this is a driver issue and not a hardware failure issue.

If it's receiving power but not data you'll need to open your computer and make sure the SATA/PATA connections haven't been loosened. Since this is a Dell, you'll void your warranty on the computer by opening it. What I really think happened is your hard disks have crashed or the IDE and SATA ports have both failed on your motherboard.