How to remove boot from MacMini? I have tried installing windows 7 on my MacMini. 

I followed following steps.


Setup went perfectly But while installing I thought of not installing it. 
So, I just restarted mac mini. 
Pressed Alt key while booting
Started OSX 
Launched Disk Utility
Removed windows partition.


But after doing all these stuff, I am facing new problem. Each time when macMini starts, I always have to press ALT while booting, otherwise it goes in indeterminate state. 

Please guide me.
According to discussions.apple.com you could also have removed the Windows partition with Boot Camp Assistant (located in /Applications/Utilities).  It may be worth trying that just in case not everything was properly cleaned up during your attempts.

After that you can use go to your System Preferences, and select your OS X volume as the startup disk.