Altium: Traces under Pads/Vias
Not a professional method but works:


Ctrl + Click on a via, which will highlight the whole net.
Right Click on the via and open Properties.
Do nothing just hit the Cancel.
Via is sent to background, select the track you want to modify.


It looks like this in Altium 15.



Once you move a track the via will highlighted and in the foreground again, hiding the track again underneath itself.