How can I determine the optimum placement of a wireless router

I am changing internet services next week from Bell Canada DSL (with an all-in-one wireless modem/router) to TekSavvy, wherein I will have a separate modem and wireless router.

Is there a way that I can plug in the router now and have it broadcast a signal where I can ensure that where I am planning on putting it will broadcast across the entire house?

Also, my router has three antennas, what is the best pointing direction of the antennas to make sure that the signal is good across the entire house?

Thanks

You can totally plug the router in now and test it out, and it would probably be a good idea to get it setup before the updated modem arrives — if you disable DHCP on the new router, you should be able to use it in your current setup, as well, just make sure to re-enable it after the new modem is put in.

As far as placement goes, can you give us an overview of the house? How many stories, what type of building material for internal/external walls, and how far away you'd like the signal to reach.

If you have a laptop you can download a (free) tool called InSSIDer.
Set up your router and walk through your house with the laptop. The software will show you signal strength and competing signals in the area. It isn't perfect, but it's a great way to identify potential dead zones and even see neighbors are broadcasting on the same channels and possibly creating interference.

Bear in mind anything you have that will need a wired connection. My router is in my living room out of necessity, as my Blu-ray player and Boxee Box need a wired link. It was either that, or start running Ethernet cable around the house.

Bahhh, thought I replied to this.

My house is about 35-40 feet long and about 25 feet wide.

The router is in one corner of the basement and the signal needs to go diagonally across the house and up one level. In the way is a set of stairs. The house is about 40 years old.

I have seen some templates for parabolic antenna things that you can throw on your router to increase the signal. Gonna have to try them out.

Weird. Metal will block a WiFi signal, but little else. Can you place the router somewhere so that the staircase doesn't block a direct line to anywhere in the house you want a signal? I had to do something like that in my house, as the kitchen and laundry room is in the exact center and the router was in one corner, so all the appliances and support structure blocked the signal from reaching the opposite corner of the house. The fix was to move the WiFi router into the kitchen and use powerline networking to talk to the wired router (I'm kind of stuck with where the wired router is).