Okay, Required programs using this method:
Root Explorer
And here's how you do it:
1. Downlod the .zip file which you will be using as you're new boot animation.
2. Plug you're phone in, mount, and drag the .zip file over to the root of you're SD card.
3. Unmount, and unplug you're phone.
4. Now on you're phone, open up Root Explorer.
5. Go to SD card, click mount R/W at the top, find the .zip file, long press and select rename. Rename it VZW_bootanimation
6. After renaming it, do another long press on the file and select move
7. Now go to system > customize > resource > and at the bottom, press paste.
8. Press home, reboot phone, and you now have a new boot animation
Side note: If you want to keep your old boot animation, just rename it to something like VZW_bootanimationold, that way you can revert back to it if need be.
And for an mp3 audio clip, you just follow the same steps above, only you label the sound file, VZW_Droid
Your welcome