I don't have any experience with Pocket Wizzards, but based on my reading of discussion in this forum, I doubt they could be used with older flash units other than in manual mode. Someone more knowlegable may care to comment.
If you look at page 313 or your D700 manual, you will see that to control remote flash with the camera popup you have to position the remote flash units in an arc forward of the camera. That might not be feasible in many venue unless your flash units were on the stage. You might use the SB800 (or SB900/910) if you want to position the flash units outside that arc. Because you can swivel the head of the SB800 you can put your remote flash in a wider range of positions. You might also note that the popup flash can only control two remote flash groups whereas the SB800 can control three groups.
You can definately control the remote flash from the camera if you use the SB600 or later flash units.
The SB700 replaced the SB600. I did not suggest that because you expressed a desire to do this cheaply. On reflection,I probably should have asked what your budget is.
I hope I have clarified your questions. I would also suggest that you not rely solely on the Nikon manuals when trying to understand the use of remote flash. Have a look at Joe McNally's books as well.