What would be a good DVD on what to be sure and see in Switzerland?

hi yes of course you can go alone and take your own time looking around at places that interest you, the best way would be for you to go to the tourist information internet side if you want to see lakes and mountains then luzern is ideal and has got a lot of history and where you can go on board of a ship across the lake it stops at different places which you can get off and you are surrounded with mountains or why not buy a travel book at whs or amazon which will give you a lot of ideas just looking at a dvd won't give you a lot of information...good luck

Yes, you can go without any tour guide.

Before tour, you collect information from various sources like.. internet, travel books etc.