You have a wonderful idea about making up for the spoiled food (that wasn't your fault and could have been an accident.
Instead of giving money, go and spend a few dollars and replace the spoiled foot and just mention that the old food was left out by whoever installed the new fridge. Don't blame anyone and don't say anymore. The less said the better.
You will immediately rise in esteem for being kind and generous and not making a fuss about this. If the landlady did this she will be most grateful and impressed that you did not even mention her name but rather handled the incident as nothing but a small oversight.
Because you are the newest you will automatically be at the bottom. Anyone would. That is part of being the new person, and that is a universal truth. Don't take it so personally, and perhaps after you fill the fridge back up with good food you will be everybody's favorite. Remember the best and most noble deeds are anonymous.
Now, how to fill your time between classes?
You can get this book on line or probably at a local librairie.
You are also interested in the opera.
Try this site:
There is much to do in this lovely city and the guide will help you.