Need to divide single column into multiple columns
For the first case you can use ROW_NUMBER then PIVOT to do this using the modulo operator to divide into columns and the result of integer divsion by 5 to group into rows.

WITH CTE AS
(
SELECT C,
       (ROW_NUMBER() OVER (ORDER BY C) -1)%5 AS Col,
       (ROW_NUMBER() OVER (ORDER BY C) -1)/5 AS Row
FROM YourTable       
)
SELECT [0], [1], [2], [3], [4]
FROM CTE
PIVOT (MAX(C) FOR Col IN ([0], [1], [2], [3], [4])) AS Pvt
ORDER BY Row


SQL Fiddle

For the second case Oracle has a straight forward syntax to achieve this with PIVOT. SQL Server doesn't but you can do this as below.

WITH CTE AS
(
SELECT *,
       (ROW_NUMBER() OVER (ORDER BY Column1) -1)%5 AS Col,
       (ROW_NUMBER() OVER (ORDER BY Column1) -1)/5 AS Row
FROM YourTable       
)
SELECT MAX(CASE WHEN Col = 0 THEN Column1 END),
       MAX(CASE WHEN Col = 0 THEN Column2 END),
       MAX(CASE WHEN Col = 1 THEN Column1 END),
       MAX(CASE WHEN Col = 1 THEN Column2 END),
       MAX(CASE WHEN Col = 2 THEN Column1 END),
       MAX(CASE WHEN Col = 2 THEN Column2 END),
       MAX(CASE WHEN Col = 3 THEN Column1 END),
       MAX(CASE WHEN Col = 3 THEN Column2 END),
       MAX(CASE WHEN Col = 4 THEN Column1 END),
       MAX(CASE WHEN Col = 4 THEN Column2 END)
FROM CTE
GROUP BY Row
ORDER BY Row


SQL Fiddle