If you can ensure that both worksheets are in the same sequence by
sorting them using the same column(s), then in a third worksheet you
can enter into A1 a formula like:

=IF(Sheet1!A1=Sheet2!A1,"","different")

This formula can be copied across for as many columns as you have, and
can be copied down for as many rows as you have. Any differences
between the two sheets will be pointed out to you in the appropriate
cell.

Hope this helps.

Pete

Personally, I would use Jim Cone's fine commercial Add-in called XL
Companion.  It's available at

http://www.realezsites.com/bus/primitivesoftware/

Vaya con Dios,
Chuck, CABGx3