I didn't have to look at your post count to see that you are a noob. It's ok.
By federal law, convicted felons may not posess a firearm. Period. No matter what degree of felony, no distinction between violent or non-violent, felony, banned, period. This is in effect unless the felony is expunged. This is where it can get interesting. The ban on felons is a federal law, but the felony can be a state felony, each with their own rules and guidelines for expungement. Now, once the felony is expunged, by whatever process is required by that particular court, this doesn't mean that the person will automatically pass a NICS check. I'm not exactly sure why, I would blame mostly beurocracy, but that's the way it works sometimes. Just because the court may seal the record, it's difficult to force all existing traces of that conviction to just go away everywhere.
I have a bro-in-law who participated in some minor burglary right out of high school. He was the lone non-juvenile involved. He was convicted of a felony, but later decided that if he had played smart and hired a real lawyer, he probably wouldn't have been. (Oh well.) After about ten years he started the process of expungement. He told me that he had been expunged and wanted me to help him buy a gun. I told him that if it was expunged, and he was eligible, he didn't need my help. I told him to go to the DOJ website and find what his record says, so he knows for sure. That was a few years ago, he hasn't said anything since.
The right to self-defense is a fundamental human right. Under the Constitution, rights are not taken away (here's the important part) WITHOUT DUE PROCESS OF LAW. There are those here who say that it should be black and white, either you are a criminal or you're not. Either you belong in prison or you don't. If you aren't entitled to all of your rights, you shouldn't be out of prison. The reality they are ignoring is, that most people released from prison don't deserve to be released. The system can't handle the population it has, much less hold all felons until they are in a position to have all their rights restored. A felony should hold significance. A LIFETIME of significance.
Now having said that, I would leave some room for rules a little less broad. I don't think Martha Stewart's felony conviction should prevent her from owning a gun. I DO agree that it should prevent her from sitting on the board of any publicly traded corporation, since that was the nature of her crime. I would be willing to listen to discussion about limiting the gun ban to only violent felons.
I have discussed this before, and been yelled at from both sides for it, but I'll say it again anyway. If I'm a cop, and I respond to the household of a former felon for an unrelated matter, (meaning, someone besides them was in trouble,) and I saw he had a shotgun behind the door, but I saw no indication that he was using it in anything besides a defensive role, I would probably look the other way. He probably has more need for a defensive arm than any of us.
Yes, they must get rid of all firearms. I have absolutely no way of knowing how this would be enforced, the fact that they were convicted of one crime isn't in and of itself probable cause to believe that they are committing another crime, (being a felon posessing a firearm,) I know that most gun owners wouldn't have too much trouble handing them off to friends and family.