Hi,
I am sorry to ask but do the fields contain data. If the fields contain varchar data then they are exported with the data in ' ' single quotes and if you feel that select * does not work then try selecting the columns explicitly, though I see no reason why it should not work. Export to a csv format and open the csv with excel. This would satisfy your doubt.
Please note that the IXF file is native to DB2 and hence you will never be able to read the contents of the exported file.
The WSF file is for work sheet format and relates to Lotus however the same can be opened in excel.
Hope that gives you some clues.
Nitin.