Hubs simply repeat all incoming packets to all ports. Switches are more intelligent, and they learn which port each MAC address is on, and then only send the packets to the right port. This means that your utilization increases. On a home network, that is usually irrelevant, as the minimal number of computers means that there's not much contention anyway. A side effect of switches is that since they aren't dumb repeaters, they actually electrically work like actual ethernet ports, and that means that you can increase the distances on your network. Again, though, in the home, that probably isn't going to make much difference.

On the other hand, getting a switch isn't all that much more expensive than getting a hub and it has the potential of effectively increasing your in-network bandwidth and allowing greater distances.

On the other other hand, hubs are nice when you're doing network debugging precisely because each port gets all the traffic. If you're trying to snoop some network traffic, a hub makes it easier because your sniffer can be on any port. (Of course, most commercial grade switches are configurable so that you can set a port that broadcasts all the packets precisely for this purpose, but you'd be paying through the nose for that for a home network.)