Hi- it's a good few years since we visited Lake Garda, stayed in Limone just across the lake from Malcesine. We found Malcesine very quaint and attractive, but noticed that most of the hotels were a way outside town. In Riva, the hotels were more obvious in the centre. It's a very lovely area, both places have good ferry links to other resorts,though we found the lake much bigger than we imagined, so it took longer to get to places than we thought. Good luck with your decision, I'm sure you will have a great time whichever you choose,
kate

Both are lovely towns, it's some years since I was in Riva but I visited Malcesine last year. Riva is mostly flat whereas Malcesine is hilly. I'm not sure what there is to do for a 16 yr old boy in Malcesine but he could windsurf in Torbole which is the next town to Riva.
As the previous poster stated it's easy to get around the lake on boats and there are lots of pretty towns to visit.

It's also expensive to get round the lake on the boats.

Riva is at the very end of Garda and apart from Torbole there is no other town in easy reach. Shopping is better in Riva but it's not so quaint as Malcesine.

Have you considered somewhere at the other, more populated end? Sirmione, Salo, Desenzano? Lots of towns there all within easy reach of each other and you could then do Malcesine, Limone and Riva on a day trip.

I would vote for staying nearer the south end of the lake as you'll be much nearer to places like Movieland Studios, Caneva World and Verona - we stayed in Bardolino when we went.

There is an excellent site for information about Garda shipping in English at http://www.navigazionelaghi.it/eng/gar/nlg.html which also includes a mind bogglingly complex fares chart!