Hello abunc and welcome to the CameraLabs forum!
Before I forget: Is your "old" Nikkor the "AF 28-105mm 3.5-4.5D IF" lens with AF (auto-focus)? This might play an important role in your decision as it may be quite sensible to use this lens on a new DSLR
Beware: A AF Nikkor cannot autofocus on a D40(x) body, unfortunately. So you'd need a D50/70/80 to use this lens!
From a visual (not technical) perspective a 28-105mm lens could be a nice lens to do what you want. The focal lenght is equivalent to a 42-158mm zoom on a 35mm film camera body. That might be a tad long at the short end though. Especially when your shooting indoors with more than just one person, you might find yourself constantly trying to step back to get the "whole picture". This is why the standard-lenses for DSLRs start at 18mm. B.t.w. there is a nice 12-24mm Nikkor zoom lens
if you need something wider to complement your 28-105mm.
On the other hand a focal length at the long end of 105mm is better for sports than 70mm or even 55mm.
And look at Bob Anderson (in this forum): He's quite happy with his 24-105mm (although from Canon)!
As to your other questions:
- The E510 can be used fully automatic, so don't be afraid to buy it
- Dust is not so much of an issue when you never change lenses, but it can creep into the body through a zoom mechanism
- Anti-shake is (very) nice, but people have made fantastic photos before without it
- Cleaning the dust requires you to blow into the cam-body with anything else but your mouth (beware spittle!). If you can do that , you can get rid of dust
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Thomas (beware: Nikon-fanboy and moderator!)
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