The Dallas Cowboys pick 18th in the first round of this week’s NFL Draft. They have many needs. Here’s a look at their top five draft needs:SafetyThere is no debate what the Cowboys’ biggest need is. Though you might question whether it’s the best value to pick a safety in the first round, the inexperience and injury history of Barry Church and Matt Johnson make safety a must-get in the draft. Free-agent signee Will Allen is a career backup and a stopgap. Texas safety Kenny Vaccaro would be the pick at 18. LSU’s Eric Reid is a second-round option.GuardGuards Nate Livings and Mackenzy Bernadeau were disappointments as free-agent signees a year ago. This draft is loaded with top offensive linemen, and the Cowboys could solidify a guard spot for years to come. Alabama’s Chance Warmack or North Carolina’s Jonathan Cooper would be the pick if either is available at 18.Defensive tackleThe Cowboys believe that Jay Ratliff will be better in the new 4-3 defense. But he is more suited for the three-technique tackle spot in Monte Kiffin’s defense. The Cowboys would like a wide-body to play the Booger McFarland role. Missouri’s Sheldon Richardson could be the pick if the guards and safety are gone at 18.Running backDeMarco Murray remains the starter, but it can’t be overlooked that he has missed games in each of his first two years because of injuries. The Cowboys need a runner to help share the load and also start if Murray is not available. Jason Garrett wants a big, physical runner who has a history of getting a lot of carries. Michigan State’s Le’Veon Bell is a favorite.Tight endThe Cowboys are happy with Jason Witten as a pass catcher. But the lack of a blocking tight end has also contributed to the poor running game, as well as failures by the offensive line. They need a physical presence to help set the edge. Two names to watch at tight end are Rutgers’ D.C. Jefferson and Michigan State’s Dion Sims.