Q: i forget my passcode and phone is disable. how i enable our phone

Connect the iPhone to the computer you usually sync with and use

iTunes on that computer to restore the iPhone.

Just connecting it to iTunes most likely won't work. Put the device into Recovery mode, this is the only way passed a forgotten passcode and disabled device. You can use http://support.apple.com/kb/ht1808 on how to get the device into Recovery mode and restoring the iPhone in iTunes. This will get passed this. You may have to remove the device from iCloud.com/#find after you turn it off, and "remove from account." if you have the Find my iPhoen activation lock in place.