ktlb4,
When is this trip taking place? You could certainly spend some time on Lago di Como and stay either in the towns of Varenna or Bellagio, which are both in the mid-lake area. If you decide on Varenna, you could look at Royal Hotel Victoria, Albergo Milano or Villa Cipressi. All of those should meet your criteria. If you'd prefer to stay in Bellagio and have a large budget, have a look at Grand Hotel Villa Serbelloni.
You might also consider Lago Maggiore and the town of Stresa. It's easily accessible and has lots of posh hotels lining the lakefront. Check the RS Italy guidebook or Trip Advisor to find something that fits your criteria. As well as touring the Borromeo Islands, Mt. Mottarone or other local sights, you could also take a day trip to Locarno (CH) via the scenic Cento Valli Railway. Whilst in Locarno you could visit the Madonna del Sasso Monastery, take a trip on the cable car to Cardada for some incredible views, stop in the Casino and try your luck, or perhaps just do some shopping at the local Bucherer store for that CH 25,000 Rolex watch that you've always wanted. After touring Locarno, take the boat back to Stresa in the early evening.
Buon Viaggio!