Took a call tonight, stuck the phone back in my pocket. Rings again and the screen is black with only a few lines and spots on it. if i press on the screen light shows up, but of nothing. phone still rings. Took the battery out and stuck it back in, same thing.
Your phone froze. You probably have too many background apps running. Normal working RAM should run between 245~275MB. If it's over 275MB, you'll experience some freezing at least once a day; your phone will definitely freeze when it goes over 300MB.
1. Uninstall some apps which are using up too much RAM.
2. change your live wallpaper to "simple kind" such as black wallpaper. it reduces RAM as well as your battery too.
3. If you use any kind of auto killer, make sure it doesn't kill any essential core programs or foreground apps.