UD,
On the Georgiana you have a no wake zone when you leave the Mokelumne most of the ways to Oxbow Marina. You'll then pass under the Tyler Island Bridge, but you shouldn't have to open that on a jet ski, but there is a no wake zone on the north side of it. You'll also pass a couple of permanently anchored boats that must be slowed down for and finally the last two miles prior to hitting the Old Sacramento are a No Wake zone. It is a beautiful ride, but would be tedious on a jet ski. I would opt for the North Fork of the Mokelumne and then come through the Delta Cross Channel Gates. It's also a nice ride, you can travel at speed and you can also stop for a toddy at Giustis.