Have you tried experimenting with the filter commands on the People workspace to see how you can get what you want? Then, when you've found out how, go back to Exporting selected individuals and repeat using the filter commands you had discovered that worked. You'll have to make note of it somewhere so you can duplicate it for export.
I just noticed you didn't want the ancestors of the spouse of the selected individual. If you detach the spouse and then use the filter this should accomplish what you want. You can then re-attach the spouse when you've finished.
To be safe, work from a copy of your tree. This way the primary copy doesn't accidentally get messed up.