^ What he said.
Rule #1 of NPS is "do not use NPS". Seriously.
When you plug in the USB cable, and act on the notification that appears on your phone, you'll get two new "hard disks" on your pc. One represents the built-in storage (
/sdcard) and will always be mounted; the other represents the removable sd-card slot (
/sdcard/sd) and will not be mountable unless there's a card in the slot. You do not get access to anything outside of (
/sdcard).
Then you can just copy files back and forth as you please. I believe you can put your music anywhere and the player will find it (I don't know for sure, as I don't use it) but I would recommend creating a "music" folder. For ringtones and notifications, you need to create the exact folders "
/sdcard/alarms", "
/sdcard/notifications", and "
/sdcard/ringtones", and place your sound files there.
As for contacts, you should create them in your Google account and sync them over.
If you want to flash your phone, or play with the firmware, you can use Odin (search the forum) and the ADB, Android Debug Bridge (ditto).
Oh, and also:
Welcome!