The previous suggestions are good.
Also turn off 2 of the three, and see if that makes a difference. Also turn off 2 of the three and see if there is an improvement. Especially with your son's. If he is running programs, like a torrent client, it may eat up almost all of your available bandwidth. Also if he downloads free or free trial software, it's likely there is some spyware that may be slowing you down also.

You can test you actual speed here:
Speedtest.net - The Global Broadband Speed Test