Distant from front wall

The front wall, although I do think speaker depth could be an issue if your speakers are box speakers that happen to be rear ported. For example, I had to put my WATT/Puppies further out into the room than my previous speakers (Tyler Acoustics) because the Tylers were front ported, and the Puppies are rear ported, and significantly deeper.

Distance is measured from the front wall to the front of the speaker baffle.
Distance From the side wall is measured from the wall to the center of the woofer in the front baffle.

Russ

In regards to distance from the wall, I have had very good soundstaging resulting from using a fibanachi (sp?) ratio to calculate the distance (i.e. 1/3, 1/5, 1/7th, etc. of the room dimension). Happy Listening,

From the center of the woofer.

Fibonacci... but your examples don't appear to be Fibonnaci numbers.

http://en.wikipedia.org/wiki/Fibonacci_number