Color LCD is the correct choice. That is the profile made for the display at the factory.
The only time you want to choose something else is if you have generated a customized profile using calibration hardware. Using a calibrator is usually important to photographers and designers doing color-critical work, but not necessary for users in general. The sRGB and Adobe RGB profiles are there for other uses (like photo editing) and must never be chosen for the monitor.
The color profile has zero effect on battery life. Scaled resolution might, but I doubt it.
The Apple Store page describes their battery rating: "The wireless web test measures battery life by wirelessly browsing 25 popular websites with display brightness set to 12 clicks from bottom or 75%. The HD movie playback test measures battery life by playing back HD 720p content with display brightness set to 12 clicks from bottom or 75%...Battery life varies by use and configuration. "
It is plausible to get less than 9 hours if certain factors are affecting the load on the computer. For example, if you've installed background processes that might use a little CPU all the time, like monitoring utilities, system customizers, or sometimes drivers for peripherals. Also, I am not sure whether the Apple test has Bluetooth on or off. In the Apple test, the movie is being watched in iTunes (using QuickTime), but if you are watching your movie through a different player like YouTube (which uses Flash) or Netflix (which uses Silverlight), the Flash and Silverlight technologies may drain the battery at a different rate than iTunes Quicktime.
I think 6 or 7 hours is OK if you are using other applications like PowerPoint or Photoshop. Anything involving graphics is going to drain the battery faster than office apps or music.
I have gotten very long battery life on trains and airplanes where there's no wifi, because I shut off wifi and Bluetooth and turn the brightness down when the cabin is dark. Under those conditions you might get at least 10 hours of battery if the CPU isn't under a significant load.
