The difference is the degree of crime. I don't know all the circumstances of your case. If you're convicted of a second-degree felony, then the crime would've been reduced to a third-degree felony. If you were convicted of a third-degree felony, the crime would've been reduced to a class a misdemeanor. That is the benefit of an attempted designation. It reduces the crime one step.
The main difference is what the attorney above explained. In reference to the job application, truth is usually a safe bet. However, if the truth hurts you, you may want to consult an attorney before answering the question. The way the question is worded can make a world of difference in how you answer the question. For example, some questions ask specifically for felonies, as opposed to misdemeanors. And some questions ask if it was a crime that you got jail time for. So it really depends..