Which lens give the widest field of view with the least distortion?

I have a Nikon D7000 and i need to take some interior photos of a restaurant. I've always been a fan of shooting photos with least lens distortions so i want to stay away from using wide angle lens. Problem is, the place is really tiny. Probably only about 600 sq and i don't have much space to work with. Which lens could i use in this little space to get the widest field of view with the least distortion?

I use the Nikkor 12-24 mm lens which gives a very wide field of view without distortion (as long as you are NOT shooting portraits). This lens is used exclusively for shooting architecture and landscapes

The link is to two shots taken using the 12-24 mm lens.

You neglected to tell us what subjects you will be shooting in such a small space. Without that information, it is difficult to give you a definitive answer

When using a wide angle lens, you need to assure that your camera's back is parallel to the walls of any architecture and the when shooting landscapes, make sure that the horizon is level

Fhotoace has given excellent advice, especially the part about being certain that your camera is absolutely level. If you tilt the camera up or down the vertical parts of buildings in your picture will seem to converge or diverge - as you probably see in newspapers most days. That happens with any lens, but is more noticeable with very wide lenses.

A wide angle in the 10-20mm range will do the job. I use a Sigma 10-20mm and provided I have the camera dead level there's very little distortion even at 10mm.
With the camera off level I use Paintshop Pro to correct distortion.

With a crop-body camera, you'll want something in the 10-12mm range. The Tokina 11-16mm f/2.8 is an excellent lens for the price. Shooting interiors with any UWA lens requires a bit of skill. Avoid extreme angles (shooting upwards or downwards) to minimize vertical distortion and be prepared to do a bit of editing in post.

The Tokina 11-16 and 11-20mm lenses are excellent lenses. Your D7000 will handle the Tokina versions with and without focus motor in the lens. To shoot properly, be sure camera is level and not looking up or down. I use a bubble level to ensure my camera is level.

The Tokina 11-20 lens distortion is easy to correct (first order distortion correction will work nicely) in Photoshop or Lightroom, although, you'll need an up to date copy of either program since the lens is so new unless you know how to extract the lens correction from a newer copy and install in an old copy of Lightroom. I would assume the 11-16mm Tokina lens is easy to correct.

I wouldn't worry too much about wide-angle distortion such barrel or pin cushion. Using photoshop or lightroom will make it very easy to remove distortion common to wide and ultra-wide lenses.

If editing the shots isn't for you, you can go to photozone.de and see exactly how much distortion each lens has.