Few more cd's/dvd's more specific to demo usage
FIM Audiophile Reference IV (preferably SACD, the cd is pretty good as well)
Telarc - 1812 Overture SACD(Just for the Cannons and dynamic range)
Blood, Sweat & Tears 3 MFSL SACD (for the horns)
Eagles - Hell Freezes Over DVD (intro to Hotel California makes a great demo)
Sting - Brand New Day SACD (Thousand years has a very deep bass line you will feel the presence of only if your speakers are placed correctly, else you won't feel it)
The Ultrasone Demo CD (excellent demo for headphones, not so much for speakers IMHO)
Dream Theater - Awake (If you want to showcase some metal/progressive rock, the first song sounds great on headphones, bass drum in particular)
Donald Fagen - The Nightfly (since I mentioned Dan before, this has to be mentioned as well)
2L Nordic Sound demo cd (You can get a free copy from the 2L website, has some good songs which give a sense of space and depth)
Derek Trucks Band - Songlines DVD (Good concert, high quality video and audio)
Chesky Demo CD SACD (Has a good track by track description on what aspect to focus on for each song)
Micheal Jackson - Thriller (ok, not the best of the bunch, but very recognizable, so it can make your equipment stand out more)
Radiohead - Amnesiac (very underrated album, has a vinyl like quality to the recording, not many ppl like it, just a personal fav of mine)
Ozric Tentacles - Spirals Into Hyperspace (Good electronic, rock, techno fusion music, excellent recording with terrific bass playing)
Stevie Ray Vaughan - Sky Is Crying (MFSL) (Chtlins Con Carne has an incredibly natural and Live sound to it, highly recommended)