Carl's right: think sticks.
If they totally ban guns and get away with it, they'll keep going, with swords and other medieval weapons being banned as well. Look at the UK, where some members of Parliament have suggested banning pointy kitchen knives!
If I were picking a non-firearm for home defense, I really like the
madu -- a double-ended spear with a small shield in the middle. It's a parrying weapon from India, that was usually made with two antelope horns joined at the butts and with the tips often sheathed in steel. I would use it with a short sword in the primary hand, but that lower spear point is the real weapon: it's great for going after feet, legs and even the lower abdomen. It's light and quick, and the edge of the buckler would also be dangerous for an opponent. I've faced the madu in the SCA, and it was a beast to deal with in the hands of someone who knew how to use it.
Away from my home, however, I'd be back to the stick. If anyone wants a quick, basic intro to stick fighting, I generally think of John Styers' classic book:
Cold Steel. His chapter on the stick is very well done and focuses on the two-handed use of the stick. I can speak from experience that a two-handed blow from a stick, with the person's body weight behind it, is very, very unpleasant to receive. I was fortunate not to have been seriously hurt.
I found that Steyrs' book is still available from Amazon, or you can ask your local librarian to get it for you from another library, if they don't have it.
Regards,
Dirty Bob