I dunno where my manual is, but the only time I use that button is when reviewing pictures in camera. If I want to delete the image currently displayed, I press "function" and "esc" instead of having to navigate all the menus. As for pointer in top window, can you clarify? Do you mean along the left edge of the LCD display? The arrow there shows up when you activate certain features of the camera. Manual white balance mode will bring up "WB" indicator, higher sensitivity the "ISO H", continuous rapid sequence shot mode the "Cnt" indicator. As far as battery usage goes, this camera can be a hog. If you run it with LCD and backlight all the time, you'll run out of battery in no time. I haven't timed it, but maybe two hours. However, if you make judicious use of power, it's lasted me a day of travel snapshots. Always carry a spare set of batteries though. Nice thing is if you run out, easy to find emergency spares at a store. I've been more or less satisfied with this camera. Image quality is good, low light sensitivity pretty good, size not smallest, but manageable, ok zoom. Pretty good all around camera, although current cameras of same new price range are now much better. I've been having some problems with the switch, and don't remove the memory card with the power still on!