"It depends" is the answer to both of your questions. I don't know of a way to give you a specific answer without knowing your complete configuration (every piece of software and infrastructure between the keyboard and the disk).
You do have choices, but you'll need to provide more information for someone to be able to help you.
The first question that jumps to mind is how are your images formatted? At least in most cases, PNG or JPG images can't be compressed enough to be worth the effort. BMP or RAW files can be reduced to 5-20% of their original size. Depending on your choices, there may or may not be opportunities here.
The next question that occurs to me is WHY is the database growing, and what does "very fast" mean to you?
I'm guessing that there are ways to significantly reduce or manage the size of your database, but at the moment I have far more questions for you than I have answers!
In theory, theory and practice are identical. In practice, theory and practice are unrelated.