Using older Nikon lenses of any type are somewhat chancy with Nikon equipment, especially with lower end Nikon cameras. I am not at all familiar with the Nikon N2000 so I can't give any advice regarding those specific lenses.
I am a Canon guy and although I am not saying that Canon equipment is better than Nikon gear, I know more about Canon, so I can make a recommendation for a setup. Any Canon DSLR camera you would consider can use any Canon auto focus lens manufactured since about 1980 (and that ia a wide variety of new and used lenses).
I don't recommend that a person new to digital photography purchase used equipment, you never know what you will get. Luckily Canon has some models which are well within your price range and which you don't have to sell a kidney to afford.
The very best way to buy a SLR is online... However, there are some crooks advertising on the Internet and the best way to avoid these rip-off artists is to buy from a reputable dealer. I strongly recommend either Adorama or B&H Photo. Both of these companies are New York based so you won't pay sales tax. They are extremely reputable and usually ship items very quickly. I have purchased many large and small ticket items from them and have always been satisfied. If you find photo equipment at a significantly lower price than either of these dealers, I would bet that the advertiser is a rip-off artist.
Although I recommended not purchasing used equipment at your stage of experience; I highly recommend getting a Canon Refurbished camera and lens from Adorama. I have purchased two new Canon DSLR cameras and had to send each in for service within the first 90 days. I purchased my next two Canon DSLR cameras as Canon refurbished units and never had a bit of trouble with these cameras. I have more confidence in the quality control at the service centers that at the Canon assembly line. Adorama carried refurbished Canon equipment and adds their own one-year warranty on that gear.
In your price range, I would probably recommend the Canon T1i camera with the 18-55mm kit lens. This camera and lens is capable of very nice imagery and also has some video capability. The price of a refurbished camera and lens is $549 (all prices in U.S. dollars) with free shipping. Although I usually recommend folks to stay away from bundles, Adorama offers a bundle which includes an additional 4GB CF Card, an additional battery and a slinger back pack. It seems to me that this is a very decent deal for ad additional $58 or so dollars. ($607 with free shipping)
http://www.adorama.com/ICADRT1IKR.html
Going up one notch in the Canon line is the T2i which has some additional capability, mainly along the video line. A new T2i with lens at Adorama runs $769 but, it doesn't seem to have free shipping. There are also some packages available with extra CD card, battery and carrying case which may or may not be a viable purchase and which will be over your $700 limit.
http://www.adorama.com/ICADRT2IK.html
Here is a quick comparison between the T1i and the T2i.
http://snapsort.com/compare/Canon_EO..._EOS_Rebel_T2i
ENJOY YOUR NEW CAMERA WHATEVER YOU BUY... Many members of this forum work with some of the highest line equipment and we sometimes forget that entry level equipment will satisfy most other photographers. All of today's DSLR cameras, even entry level models, are capable of some very good work. I would expect that the T1i or T2i have better capabilities than a DSLR camera from twenty or so years ago which people thought was a great bargain at $20,000 or so!