It is not all haggis, deep fried Mars bars and coronaries on a plate! That is for special occasions, like days ending in a 'y'! ;-)
Seriously though, in the larger towns and cities there will be a wide choice. Some great lamb and beef comes from Scottish farms (also English and Welsh farms), which will be available in most of the places you are likely to visit.
Out in the country choice will be limited, but it will generally be a mixture of dishes. Not every body likes seafood, like yourselves, but there is likely to traditional Scottish/British dishes and also Italian on most menus.