how to delete the iTunes from Mac OS Lion?

Technically, you can't. Or rather, Apple doesn't want you to. iTunes (in OS X Lion) is considered part of the system. In other words - integral to how OS X operates. The only way to delete iTunes is to go through the following steps.

- Open the Applications folder.

- Select the iTunes app.

- Use the keystroke Command I (for Get Info)

You'll notice a new window appears that tells you various info about the item. At the bottom of the window, you'll see a permissions list. This is technically supposed to be for OS X only. (Users aren't supposed to touch it, as it might damage part of the system.)

On the lower right-hand corner of the "Get Info" window, there a small lock icon. Click this. The computer will now ask you to authenticate with your login password. Do this. The item should not be unlocked, and the icon will show this. Now, look at the list. Select the user named "wheel". Change the permission from "Read Only" to "Read and Write". Now click the lock icon to lock the item.

You may now delete iTunes by placing it into the trash, or by using the keystroke Command - Delete. Empty your trash. You have now successfully deleted iTunes from your computer.

Note: the only way to now recover iTunes is to download it from Apple's website. The only current version is iTunes 10.4, which has has bug issues. Make sure you're absolutely willing to do this and note that any iPod, iPhone, or iPad devices will be unable to sync until you reinstall iTunes.