SELECT Row_Number() OVER(ORDER BY UserName) As RowID, UserFirstName, UserLastName
FROM Users
From which it will yield a result set with a RowID field which you can use to page between.
SELECT *
FROM
( SELECT Row_Number() OVER(ORDER BY UserName) As RowID, UserFirstName, UserLastName
FROM Users
) As RowResults
WHERE RowID Between 5 AND 10