Welcome, leejtb. Reading your posting reminded me so much of my son's story when he was 6. Truthfully, there could be a lot of reasons why your son has trouble paying attention in class, and being bright and bored could explain why he has trouble sitting and listening, but the hitting part really does make me question whether something more is going on. It sounds like he's rather impulsive, and acts before thinking of the consequences. My son was eventually found to be highly gifted, and to have ADHD. He wasn't intentionally trying to annoy other kids, but he often did things that irritated those around him (ie, even when sitting at a desk, he might tip the chair back on two legs, and bump the child in back of him...) I don't know if you've ever expressed your concerns to your son's doctor, but it might be a good thing to do. You can also look at sites like www.help4adhd.org and see if the behaviors sound familiar.

In so far as homeschooling, the rules vary by state. I'm not from NJ, but if you do a "google search" for "homeschool New Jersey" you'll probably find a wealth of information. If your son is willing to work with you, then clearly 1:1 will provide undivided attention, and your son will likely learn a great deal more than if he stays in the kind of classroom you described.
You might also like to join Greatschools Homeschool Parents Group at community.greatschools.net/groups/11543