It is possible! Now that you can make a script tool into a button on the toolbars its even better. You would have to tell the script which layer has the selection but thats the only step for the end user.
A selection is made,
script gets a list of the layers in the mxd,
select by location on each layer with selected layer as input,
read other layers (cursors honor selection) and write the values out to a CSV.
You can export straight to an excel file instead of a csv but you have to use win32com and that might be more complicated than is worth dealing with in this case.