the scale only refers to the graphics - the numbers are what it calculated. as with any analysis tool, any errors or incorect assumptions put in the begining propagate to the end. if the answer doesn't seem right, double check the inputs.
The value listed for the deformation is the actual result. The deformation scale is simply the scale factor used for visual purposes. Typically deflections are so small that thy don't show up graphically very well, so SW scales them so we can see them.
The other question, is the result valid... maybe, maybe not. How does the result compare to a hand calc? Your loading might be in the realm of "large deformation" therefore non-linear. Traditional beam calcs are not valid and static FEA that doesn't take into consideration large deformation is invalid. Ultimately, the best comparision is with a real world example. How does the FEA compare to that?