How do you stop a computer PC windows 7 from freezing when it starts up after about 3 minutes it opens in safe mode but not regular mode?

Use the up/down arrows to move it to regular mode. The computer will start normally at that point. It sounds like you are shutting down your computer without going to the menu and highlighting "turn off". When you do this the computer starts in safe mode because it wasn't shut down properly. DO NOT shut down with the power button. If you have a laptop you can program it to turn off when you shut the lid.