You cannot remove the "Search" button. Since the search screen is only able to show a single string of text for 9 results, I usually use the Search button to take the user to a new screen (poster or grid) with the full search results with expanded metadata.
My Channels: http://roku.permanence.com - Twitter: @TheEndlessDev
Instant Watch Browser (NetflixIWB), Aquarium Screensaver (AQUARIUM), Clever Clocks Screensaver (CLEVERCLOCKS), iTunes Podcasts (ITPC), My Channels (MYCHANNELS)