I don't think you can, Even you can strongly suggest you don't do that on any true View finder camera,
Because the viewfinder won't and can't show what have been crop and you will crop something you want to keep when you take a picture.
To Crop a picture is better to use a software to crop after you take the picture,
so you can chose what you need and what you don't want.
Nikon have provide a Free software call ViewNX/ViewNX2 for all nikon user,
you can crop you image from there, it got a wide range of crop factor you can chose.

Not as far as I know you cant, what does it say in the manual ??

There is an internal battery that keeps the date and such but if it will not turn on with a full battery, there is a problem. Here is my experience. If you are NOT using a Nikon battery, the D700 sometimes will not work. Not sure why but I've had batteries in a D300 that worked great, that were off-brand. However, put those in the D700 and you get nothing. Also, they don't work in the body chamber BUT they will work in the MB-D10. Weird. But if you are using an off-brand battery, try a Nikon before sending in for repair.

try cleaning the contacts of the battery (ONE at a time, do not short it out), and/or the contacts in the camera.

Use swabs and Eclipse fluid, easy enough to do as llong as you dont go mad at it, plenty of online info on how to do it.

If your NIKKOR is Ai or Ai-s model it's work perfectly.

No. It does, however have a setting so you can take bracketed photos and make an HDR image out of them. You can also use a RAW image for smaller dynamic range coverage. To be honest, you get a better result from using stand alone software than in-camera. I am not at liberty to make suggestions on software via this forum, but a little time Google searching and you can probably find some good candidates.

No

Read this:
http://support.nikonusa.com/app/answers/detail/a_id/17802/~/d700-firmware%3A-a%3A1.03-%2F-b%3A1.02