I think its the lookup format
I recently had a similar problem. I had a look-up table for standard messages containing msg # and text - which was joined to another table by msg #.
In the main table, I entered lookup info that pointed to the lookup table. This was nice for data entry because it now provided a dropdown box containing all the options you could select. However, when reporting, it showed all values for both msg# and text - and highlighted in black the value that was contained in the field of the main table. My query showed the straight data contents, just like i wanted on the report, but when i created the report (with the wizard), it was incredibly funky - and acted more like a form than a report.
The fix here is to go into design mode on the report and double click on the datafield in question.
I uploaded two small bmp's that show the weird report results and what the data format and source windows look like when you double click on the field in the report (design mode). By changing the contents in the column count field (and maybe some others) you will change what winds up going to the report.
The only way I could completely fix this weird report problem was to get rid of all the look-up entries in the design tab of the main table -now it all comes out like regular data.
