Wireless network/Router question

[gatoconbotas]

So, my family has had this very convienient, nice wireless network set up for roughly 3 almost 4 years now, and I've never had a problem with it.
My laptop is only about two years old, so it shouldn't be that.

Here's the issue: All of the sudden, I get NO wireless service, at all in my house.
Everything is connected all fine and dandy. All of the cords are completely in, everything is tight and happy.

I have NO wireless service at all. I'm sitting right next to my wireless router, and have no signal.

My question is:: How often do you need to replace the wireless router? How long does it take for them to like...quit?

I'm 99.99% sure that it's not my laptop, because
a)my Xbox360 can't connect to Xbox Live either...and it's wireless and I haven't had a problem before. and
b)I tried using a USB wireless adaptor that came with the router and it won't work either.
So, considering my xbox360, my laptop, and the usb adaptor all don't work...that narrows it down to the router.

So..again. How often does a router need to be replaced?

Any help would be mucho apreciado.
Thanks