Thank you for answering so fast.
1. I am using Windowed (Fullscreen) mode all the time, save for the times when i actually tried to fix the issue by using the other two.
2. For some reason i failed to understand correctly the aspect ratio stuff last night, probably cuz i was damn tired of battling this issue all day long. Thank you for the explanation, i will look into it and do some tests. Will report my progress here and hopefully i won't need your third point, as it isn't the best solution available

Best regards,
Food