Per you question about getting people to order online more, I think your critical problem is the button color and font. On my laptop and monitor it is almost unreadable. If you are married to the green button, then change the letter color to black, then it will pop. The White lettering on the green button is hurting you in my opinion. The other option is darker button color with the white lettering. I think you need to address you current combination one way or the other
Brilliant way to capture the postcode
Prominent, clean, straightforward. Think of this cleanliness as you try to address your Call To Action issue on the next page.
Why is the font so small. I think the homepage would be much more appealing with larger font and less words, right now it looks cluttered. I would also make 3 easy steps to order food online the focal point of the homepage, by moving it to the middle and making it big. It took me a little while to find it as I wasnt sure what the concept of the site was at first. I did like that you had the enter your postcode here. Honestly all the homepage really needs is "3 easy steps to order food online" and the enter your postcode. Put the names of the actual restaurant on the page where people would see them in their area, because people really only care about new restaurants being added if they are in their area. The same goes for the reviews of those restaurants, maybe have a list of the most popular, but I would only show reviews after the restaurant has been clicked on.
Also maybe its just a west coast thing, but I would use Zip code, rather than postcode, unless this is not an American site.
Great concept as online ordering is becoming a huge market.