i can't boot my mac mini a1347. when i start my mac mini the display shows as attached file.please help me.

What OSX version are you trying to boot from?

You need OSX 10.6.3 or later.

If you have Lion or later:

- Try resetting the SMC and NVRAM/PRAM

Intel-based Macs: Resetting the System Management Controller (SMC)

About NVRAM and PRAM

- Try starting in Safe Mode

OS X: What is Safe Boot, Safe Mode?

- Boot to Recovery and repair the startup disk

OS X: About OS X Recovery - Apple Support

- If it is repairable reinstall the OSX

How to reinstall OS X on your Mac - Apple Support

- If you do not have a backup use disk utility to restore the internal disk to an external disk so you can try to recover data.

Then format the startup disk and do a fresh install of OSX