If you are going to back up commercially made blu ray movies onto blank blu ray discs, you'll need a decryption/ripping program. The three main ones that we recommend are AnyDVD HD, DVDFab and MakeMKV.
DVDFab has a free section that will work for this even after the trial ends. That part of the program is called DVDFab HD Decrypter. It may not be updated quite as quickly as the commercial section.
MakeMKV is free while in beta, and has remained in beta for years now. It can convert to mkv files for you, or you can use the Backup option and put the entire blu ray movie onto the hard drive.
For burning data files or movies to blu ray discs, we recommend ImgBurn. You should use UDF 2.5 file system when burning blu ray movies, but ImgBurn will recognize that format of video and will ask to change settings for you if you do not have it set properly. ImgBurn is free to download and use.