I want to understand some Export options.

Structure:

"Add DROP TABLE" will add a line telling MySQL to drop the table, if it already exists during the import. It does NOT drop the table after your export, it only affects the import file.
"If Not Exists" will only create the table if it doesn't exist. Otherwise, you may get an error if the table name exists but has a different structure.
"Add AUTO_INCREMENT value" ensures that AUTO_INCREMENT value (if any) will be included in backup.
"Enclose table and field names with backquotes" ensures that field and table names formed with special characters are protected.
"Add into comments" includes column comments, relations, and MIME types set in the pmadb in the dump as SQL comments (/* xxx */).

Data:

"Complete inserts" adds the column names on every INSERT command, for better documentation (but resulting file is bigger).
"Extended inserts" provides a shorter dump file by using only once the INSERT verb and the table name.
"Delayed inserts" are best explained in the MySQL manual.
"Ignore inserts" treats errors as a warning instead. Again, more info is provided in the MySQL manual, but basically with this selected, invalid values are adjusted and inserted rather than causing the entire statement to fail.

Knowledgebase