Well, you can write watching movies as a hobby in your resume but only if it is relevant. For instance, if you are applying for a filmmaking job you can write it and if you're applying for a normal job then you should not write it. It is all about where you're applying and if you write it in your resume is it relevant to a job you're applying for and will it help me to get selected. These things you should check if you want to write "watching movies" as a hobby.