Any *FILE object on the AS/400 is a DB2 table. To get a list of the *FILE, or DB2 table objects you can use the ‘DSPOBJD *ALL/*ALL *FILE’ command.
To copy a DB2 table to a Windows system he can use FTP, or instead of that he can use ODBC/JDBC to access the data on the AS/400 directly. This way the data is up to date.
To convert data from the AS/400 he can use the CPYTOSTMF and CPYTOIMPF commands. FTP will also convert but not binary and packed decimal columns. There are also conversion utilities available that will do the job. Using these commands he can write the converted table to the IFS and copy it from there to his Windows system through network serving (AS/400 function) or through Client Access.