Are Beagles stupid?

We bought a new purebred beagle pup almost a year ago, had her spayed, and have kept her as a house dog. She's a lovable little dog, very affectionate.

But there are two big problems. She'll never quit eating, and if food was kept available she wouldn't quit until she got sick. We can't walk away from our table even for a second if there's food on there - she'll jump up and eat out of our plates. This, no matter how much she's been scolded, threatened, and punished for doing it.

And - we can't housebreak her. We've tried everything and she just won't learn. We can put her in the back yard for hours, and she's likely to dump on the rug within 5 minutes of coming back inside. It's like when she has to go she just goes, no matter where she is. We've tried rewards and punishment, and she won't even go to the door first and give us a chance to put her out.

We've had dogs all our lives, including some very good ones, but this beagle has us baffled. I'm thinking she's just not very intelligent. Is that a problem with the breed?