I have two excel files with the same structure: they both have 1 column with data. One has 800 records and the other has 805 records, but I am not sure which of the 5 in t
Excel has this built in if you have an excel version with the Inquire add-in.
This link from office webpage describes the process of enabling the add-in, if it isn't activated, and how to compare two compare two workbooks - among other things.
The comparison shows both structural differances as well as editorial and a lot of other changes if http://office.microsoft.com/en-us/excel-help/what-you-can-do-with-spreadsheet-inquire-HA102835926.aspx