Better wireless signal/router

[metamorphpwner]

Hi,
I've currently got a netgear 834g and it's failry good for signal downstairs and a lot of the time it's ok for upstairs in my bedroom, but it does quite often become terrible.

Would upgrading the antenas on this router make it much better for signal or is there an amazing wireless (&ethernet) router i could look at?

This is for devices like ipad/blackberry playbook/ phones and ipod touch(s). PC/consoles are wired.

Been looking at the Yagi antenas that you can get and wondering if they'd be any good for upgrading to?
Something like THIS

 

[bremen1874]

The Yagi you've linked to (and shouldn't have, see forum rules) is a directional antenna which isn’t really what you want.

You can buy high gain antennas that just look like bigger versions of the existing antenna which could help with your situation.