You can open your Notifications task bar and then swipe the notification you wish to delete away by swiping it to the right. You can also hit clear to clear out all notifications at once.

You will need to use your USB cable. Before you connect to your pc, on your Note, go to Settings, select More under Wireless and Networs, then select USB Utilities, select Connect storage to PC. Plug your phone to your pc and then select Turn on USB Storage. Copy over the files you want. When you are done, select turn off USB Storage and then you are safe to unplug your phone.

You can transfer your music from your computer to your phone via USB cable. You must select the USB setting on your phone to mass storage. You can then browse your phones file directory and copy any files to and from your phone. I would suggest creating a folder called Music and drop all your music in there.

It sounds like you will need to do a hard reset on your phone. I had a similar issue when I just upgraded my Note. It froze on the ATT boot screen. I call into Samsung Support and all they told me to do is a hard reset. To do so, power down your phone, once it is off, hold the volume buttons up and down then hit the power button. Continue to hold the buttons until you get to the bootloader screen. Use the volume button to scroll down to the hard reset/ wipe all data option. Use the power button to select it and then follow the options after that. It should only take a few minutes to do. This will not remove ICS from your phone. This will remove all of your user data, so if you can, back up everything you can before hand. Also, make sure to remove your SD from your phone if you have one.

Good luck