actiontec gt704wg and blocking p2p applications.....

i have a wireless network setup using a actiontec gt704wg modem/router
and want to block p2p application like limewire, ares galaxy and
bittorrent programs from being able to download on this network. the
girlfriends two daughters live next door and we permit them to access
the internet through our wireless network via wep encryption and mac
address.

the problem is, the girlfriends daughters boyfriends like to download
tons of music and videos. they have been ask a few times to not do this
seeing it is not there network. i just found out recently that they have
been downloading music again.

i know i can just yank the mac address from the router and they lose all
connectivity but i dont really want to do that. i would like to block
the p2p applications that they use from accessing the network.

is there a way to block ares galaxy, lime wire and bittorrent programs
from accessing the network with settings in the actiontec gt704wg
modem/router. if so how can i do this?

i have googled for some help and have not found anything yet (im still
looking).

any help would be greatly appreciated.

bob brozewicz.