As a big fan of RDBMS, I would say stay away from MySQL, it can be convenient but it's generally crap. (Citation: ALLOW_INVALID_DATES) If I had to use an open-source DB it would be Postgres all the way.
Programming language? For you, I'd suggest Java based on your familiarity with C#. That would open you up to doing both web and "fat client" development and as a bonus your fat clients would be cross-platform.
I am sure there are pupils like you and possibly I was like this too (albeit I doubt that I ever had motivation and ability), yet neither knowledge in particular subject is all, nor claims of knowing more than a teacher are always correctly depicting reality. I am not a teacher but I do teaching at work by virtue of having students assigned to me for a year to do some menial jobs - they should be learning the right stuff mostly programming but more so around programming - because as far as I can tell nothing has changed much since I started - programming is a vital but minor part of developing software(*). I regularly fail to know all details that my newbies know about any chosen programming language yet I beat them every time on the actual programming and developing albeit I have to google more than they do. This will change of course and part of the course is for them to learn as much as possible. The point is - you may know all details but as so often in case of cohders - you fail to see the bigger picture.
* - some things changed since I started though - the division of work changed thanks to progress in communication technology which may make coding (and other things) being done in far away places (or in another office which is just the same if I do not know person doing the job). The system people cut jobs into small pieces and let Turks do the stuff for 10$ an hour. Yet I doubt that any big project can be done effectively only by outsourcing. If a company is a software house delivering software solutions then they most likely need to have in house competence in coding as well as developing, project management, communication and cooperation culture, decision making skills, presentation skills and much more. How often project fail because any of these were not there. Then again it all depends on the project of which part is people doing it.
Bureaucracy is not a good solution to the problem but it seems the only one that can prevent many accidents. It seems to me that this attitude made nuclear industry surprising safe. At least when one does not think too much about waste disposal.
3strikes are for wankers and liberals - let them criminals make small stones from big stones for few years and then release them into free marketplace with a permanent criminal record. That will teach them.
If they are abroad drone them down - no need for a court order then.
That said, their hardware and software both have their fair share of frustrating warts. Finder sucks, Yosemite broke GPU-switching and some of the newest Macbooks suffer embarrassing Bluetooth vs Wifi conflicts. Some good, some bad, Apple seems to be the way they've always been.