You should be able to use a second wireless router as a network extender, to give you more range. Dead easy to set up with an AirPort. Not sure about other routers.
what would be a suitable wireless modem/router (with voip) that has the widest coverage? It should be strong enough to cover a lot of rooms through brick walls. My family lives next door to my home so it should also be accessible from there too!
I was thinking of iiNet Bob but I'm not sure if the signal from that is strong enough...
anyone have experience with modem brands to make some recommendation?
iPad 64 3G , Macbook Pro 4.1
On a serious note, I think the distance in a numeric form would be helpful in solving your question. My DIR-300 covers every room in the house, and its biggest distance possible in the house, my netbook receives 48-54Mbps on 'Good' or 'Very Good'. This is through approx 2x double brick walls, and 3 single brick walls.