The "All Drosophila" option is a group of databases. Specifically it uses the databases:
fly_factor_survey.meme
flyreg.v2.meme
idmmpmm2009.meme
dmmpmm2009.meme
Which are all included in the motif databases download available at:
http://ebi.edu.au/ftp/software/MEME/index.htmlIf you want to determine what databases are in each option you can open the motif_db.csv file in any text editor and look at the space separated file names before the first comma on each line.
You can run Tomtom with all the fly databases with the command:
tomtom query.meme fly_factor_survey.meme flyreg.v2.meme idmmpmm2009.meme dmmpmm2009.meme
The full command-line documentation for Tomtom is available here:
http://meme.nbcr.net/meme/doc/tomtom.html