you should provide more info ...
I'll guess your using WinXP with a 32MB card?
It could be a DirectX issue. DirectX does not like to share with multiple apps and so 3DS will have some issues.
The initial load time is definately a DB issue. You can do some things to hide it, like a load a bitmap on the first line and show that while loading the rest of the game.
The crappy screen in 3DS after your screen saver is an indication that the data in your 3D card was currupted. This is why I think its a DirextX issue. When DB places data into the card and then exits, the 3DS data is lost too.