All the tutorials and documentation I have been able to find so far require physics be done in the Blender Game render engine. But when I have Blender 2.70’s render engine set to Blender Render I see a Physics button in Properties, and when pressed there are several options under “Enable physics for”. Does this mean there is a physics engine also available for Blender Render? If so where can I find documentation for how to use it?
Does this mean there is a physics engine also available for Blender Render?
Yes, there has been for a while
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.66/Rigid_Body_Simulation
http://wiki.blender.org/index.php/User:Sergof/GSoC2012/Documentation
https://www.youtube.com/results?search_query=blender%20rigid%20bodies&sm=3
Thank you for the links 
There is a control I cannot find documentation for. This is Physics > Rigid Body Collisions > Source
In this selection box there are three choices: Final, Deform, and Base. I need to know what these are. I do not see this under Shape: in the video tutorials for Physics in Blender 2.66 so I suspect this came in a later version than that.
https://developer.blender.org/rB2260a7d
Read the tooltips
See the attached example. The top box has a shapekey and solidify modifier that both change the shape of the object
For ‘Base’ neither of these are not taken into account when calculating collisions
For ‘Deform’ the shapekey is taken into account but not all the modifiers
For ‘Final’ both the shapekey and modifier are used to calculate the collision
Attachments
source.blend (112 KB)