The different colored circles represent approximate signal strengths. The strongest signal will be within the innermost oval. In general, reception is possible via a normal Dish antenna as long as one is within the outer oval. A larger antenna would be required to have a chance of reception outside the outermost oval.

Spot Beam 11 is the HD feed on 129W and spot beam 41 is the SD feed on 110W. Different sats = different positions = different shaped beams although position is not the only determiner of beam shape.

FYI when you access the point dish screen (menu 6 1 1 or yellow 9 2 (hopper)) it displays the sat and TP for the last channel you were on.
On that screen you can select to view which sat or TP you want to see but when you change channels during normal viewing , its the receiver's software that determines which ones to "look" at using info such as ,which satellites are available (switch test results) and what programing you are authorized to receive.
It will even sometimes automatically shift to the SD signal if the HD one is lost.