How to Stop Intel Imac From Booting From DiskWarrior DVD

This one is about as off topic as I get. I post it because I just wasted the last two hours of my life figuring it out, and I hope to save someone the frustration I just had.

I made the mistake of setting my Intel iMac to boot from my DiskWarrior 4 disk. I'm not quite sure why I did this instead of just holding C like I usually do, but I'll sure as hell never do it again! I couldn't eject the disc or boot back to the system. I scoured the Internet from my phone and tried the many suggestions I could find:

• Holding Option while restarting
• Holding the left mouse button while restarting
• Pressing the Eject button while restarting
• Messing about in the drutil window

None of it worked. I had just decided I would take the damn iMac apart even if I destroyed it in the process, when it occurred to me to try one last thing. Here's what worked:

Unplug everything from the computer except the wired keyboard (connecting directly) and the power cable. Then hold the Option key on restart. Finally! This let me select the hard drive instead of the DVD.