I wrote an application for importing an Excel spreadsheet into MySQL. It meets all your other requirements except specifying columns to import, but it will import everything very fast and you can ignore or remove columns you don't want easily enough. In my biased opinion it is simply the most accurate, easiest and fastest way to import Excel spreadsheets into MySQL.
You can verify that it works with your data before purchase. It will load all your data except some random records will be blank until licensed. There are 2 versions of the program available. An easy to use GUI version and a command-line version which will allow you to automate and append your data to the table. It can handle all versions of Excel and MySQL Server. The process can be fully automated. Once you have the command-line version of the program called from a bat file or your favorite programming language, you can use windows task scheduler to schedule it. Excel2MySQL is capable of handling huge Excel spreadsheets.
http://excel2mysql.net

INSERT
statements (in a separate sheet), which then could easily be exported as*.sql
files. Wouldn't that be an option? At least it would cover all requirements you've listed ;)