Is it OK to look even though you do not touch?

I have heard people say things like, “It is ok to look at the menu as long as you do not order.”  This is said to justify looking at the opposite sex or even to look at porn. How would you compare this thinking with the following passage?

“You know the next commandment pretty well, too: ‘Don’t go to bed with another’s spouse.’ But don’t think you’ve preserved your virtue simply by staying out of bed. Your heart can be corrupted by lust even quicker than your body. Those leering looks you think nobody notices—they also corrupt.

“Let’s not pretend this is easier than it really is. If you want to live a morally pure life, here’s what you have to do: You have to blind your right eye the moment you catch it in a lustful leer. You have to choose to live one-eyed or else be dumped on a moral trash pile. And you have to chop off your right hand the moment you notice it raised threateningly. Better a bloody stump than your entire being discarded for good in the dump.  Matthew 5:27-30 (MSG)

Should you refrain from looking?  How can you stop yourself?  Are you willing to respect God’s Word in your actions?