problem:

displaying list of bday boy/girl in next (30/ according to your own choice ) days from the current date.

solution:
im using the sql to select the date of birth, for displaying, you can use whatever you want, like gridview, datalist etc.

hereby the sql command:

SELECT     DateOfBirth
FROM         someTablename
WHERE     (DateOfBirth < GETDATE()) AND (DATEDIFF(d, GETDATE(), DATEADD(yy, DATEDIFF(yy, DateOfBirth, GETDATE()), DateOfBirth)) BETWEEN
                      0 AND 30)

it will return the list of date of birth from the current date.

for reference of the sql command:
http://msdn.microsoft.com/en-us/library/aa258269%28SQL.80%29.aspx