They are not interchangeable for me!
I need to get home to cook dinner. I would NOT use "the" there unless we had already spoken about a dinner party or something that I had prepare.
After working in the office all day, I actually like to cook dinner. It's fun and relaxing for me. I would not use "the" there either. I would only use it in something like "I actually like to cook the dinner that my family has been looking forward to all day." (Because I'm such a great cook, I guess.)