Looking at all of the writing about driving in Italy, on here and elsewhere, there is a definite concentration on the great mountain passes. Whilst there is no doubt that driving over the Stelvio Pass etc are spectacular there are more great driving roads once you get into northern Italy.
In my recent tour I included driving along the shores of five different lakes. Sadly the weather interfered with the first couple of lakes, its difficult to get a feel for a road when you are struggling to see it! The drive up the western shore of Lago d'Iseo more than made up for it though.
What made this road, in part, was the fact that the main road up the lake is on the eastern shore so most of the traffic heads that way. Although I did get some traffic it was possible, for a large part, to set my own pace and enjoy the drive.
The next lake over is probably the most famous of them all, Lake Garda. The drive up from Salo to Riva is featured in a number of articles and was used in the opening sequence of Quantum of Solace.
The road isn't as tight as the one around Lake Iseo, although it does have its moments, it is also a fairly major route so there is noticeably more traffic. The main feature is the tunnels and galleries. There is the initial temptation to take the Hammond approach to tunnels, drop the windows, drop a gear, and floor it, but there are so many of them that it loses its appeal.
Perhaps there is a better time to travel than lunchtime but the traffic really got in the way of the enjoyment in parts. Its not that I wanted to speed along, just being able to maintain a speed and enjoy it rather than having to spend time on the traffic would have improved things. I can't complain though, the views are spectacular, especially out of the galleries, and you have to marvel at the engineering used to create the road.
We stopped overnight in Limone Sul Garda and completed a circumnavigation of Lake Garda the next day. The traffic was, if anything, worse around the top of Lake Garda and down the eastern shore so I'd probably avoid it in future and either drive back down the west or look for an alternative route over the mountains to the east.
On balance I'd recommend driving the lesser lakes rather than the main ones. The road less travelled is a more pleasant drive. This could be helped by picking less popular times to travel but if the trip is also your main holiday you do want to be getting up at the crack of dawn just to get clear roads.