You can pull down the notification bar with any app open. You don't have to be at the home screen.
No.
It means that it wants you to rate the app which it showed the notification for to let others know if it's good or not.
You might need to check your settings and see if you may have turned off notification sounds. There's also the possibility that an app is disabling your notification sound.
Try downloading the ZEDGE app from your market place. It is a free app with free ringtones.
I got a notification that it is sold to Yahoo. So is it renamed or completely stopped or what?
You can't delete the red numbers because it means the app has some sort of notification. For example if the app store app has a red number on it it means that there is an app that needs to be updated. So the only way to get rid of the number is to check up on the app.
yes two big hearts
You just hold down a Pokemon on the app and some or no hearts would show up.
Hold your finger on the notification until it pulls up the option to go to the application. From that application, left swipe across the "Show notification" line, which will pull up a confirmation that you wish to disable flash notifications from that app.
If you are on the lock screen, you should be able to see a notification with the little Skype app symbol on it. To answer the call, click on the little app icon and slide across. That should work.
If you want your notifications for Facebook to continue regardless of the Facebook app status, enable the Facebook Notification Center. Settings->Notifications>Facebook