Video Overlay Software?

Hey everyone! I currently have all of the Adobe Collection including Premiere and After Effects, but I have two videos I need to over lap and have the ability to toggle the transparency between the two on the fly. Basically I am looking for a different program that I could upload two videos and have them on top of each other with the ability to turn off the top layer and turn it on again (not an adobe program) I am going to have this for my boss who does not know Premier Pro or After Effects or have access to them. Any help would be great!!! Thank you in advanced.