This is my first BB and prior to this, I would always press the end button to turn the backlight on for my cellphones.
I noticed with the blackberry, lets say you left an app open and the screen when black; you come back later and want to turn the backlight back on, using the end button will exit you out. I've tried using the pearl, but that often brings up a menu or selects something.
What i've done so far is assign the left key as nothing and I click that.
I usually just push the trackball in to wake my device. Haven't had any problems as far as selecting something inadvertently. The odd time the menu will come up but it's not really a big deal. For the most part I dont leave any apps running on the homescreen and I also have a password lock so it doesn't matter what key i use to wake.
Try using the mute key on the top to wake the device. That shouldn't do anything to interfere with any apps you have running and at least you'll still have use of the left convenience key.
Any key works!
I kept noticing that when I dialed manually from sleep, that I was missing the first number (or letter). Turns out that no matter which key you press, that keystroke does not input a character, it just wakes her up.