Various triggers will work, I use a Flash Wave III. However, with many triggers, the TTL feature on the SB-700 will not be used. To get TTL with a trigger, look into the Nikon SU-800, "Wireless Speedlight Commander". You can use that unit to set flash exposure compensation, too. It comes with two gels.
Footnote: the Yongnuo YN560-III only requires one trigger, the one on the flash. YN560 sells the triggers in sets of two for c. $35, but you will only need one for the YN560 III, so you will have an extra one!
On the D7000, when you pop-up the on camera flash and then press the flash button again you will access the flash exposure compensation. This is an important flash feature to know about. As mentioned above when using triggers or the pop=up flash to trigger off camera flash, select the commander mode, set the on camera flash to"- -" and A to TTL where you can also set flash exp.comp.
Here are the steps: From the Custom Setting Menu scroll down to e Bracketing/Flash. right click on that then scroll down to e3 "Flash control for built-in flash", right click and scroll down to CMD Commander mode, click on that to get to the options mentioned above. Next to the "Built-in flash" selecting " - - " will shut off the built in flash as your main flash source turning it into a trigger flash.
I thought the range of the SU-800 was 66'. Here is a video showing 90'.