Yes
no, you would have to get a nikon module
and nikon camera can use a nikon lens, try a D3000, a D50, or a D9
Yes as long as it's not pre AI
Yes, pre AI lenses may cause damage though
Read the user guide
Yes but older AF lenses that do not have an autofocus motor in them will not autofocus with the D5000.
The Nikon D50 digital camera costs $1899.66 at Amazon. Yahoo sell it for much less at $599, eBay sell it the same price as Yahoo, but body only without lens.
A review of the Nikon D40 and D40x digital cameras by Nikon expert Thom All of those things come into play when choosing between a D40 and a D50, You can find the full comparison of current Nikon DSLRs here if you want the full list.
It has an "F" lens mount. source: http://www.dpreview.com/reviews/nikond50/page5.asp
Getting a Nikon 124res Camera flash will give you great light in very dark settings.
Nikon flash cameras are usually known to be expensive. One of the last models to come out, the Nikon SB-800, can cost in the neighborhood of up to $350.