Wireless N + G together

I have a new wireless N router one of the features it can act as an extender/access point.

Since my imac has the poorest signal and is the only N compatible PC in my household would i be better using it beside my Mac as an extender. My main concern with this idea is not getting the advantages of WIreless N if the main router is still G.

Are they both pure routers and you have a separate ADSL or Cable modem, or is/are one or both Modem-Routers?

Your router will only work as N or G - it cannot work as both simultaneously unless its a dual channel system like the new Apple Extreme basestation. This means that it will work at the speed of the slowest connecting device.

If you have a mixed network, and you need the N fucntionality for eitehr range or speed, use tow networks - one for each type of device.