From the UK
The drive is long from South-eastern England, but it is doable (we've done it before, and will do again for the wedding). To drive from Camberley takes about 15 hours, which can be one long drive if you share driving duties, or broken into a couple of days if you want to explore the beautiful Alps, the Black Forest, Alsace, etc.
Once in Italy (hire cars)
Car rental is available from the airports, booked in advance is affordable and undoubtedly the most convenient way to move around. This isn't Naples, driving in the north isn't too dissimilar to the UK, don't be put off!