The film option is for emulations of real negative films. The digital film option is for emulations of cameras that provide their own emulations.
Personally, I never use the digital emulations. Coming from an LF photography background, I’d rather use “real film”. My personal favourite is Fuji Acros Neopan 100.
As I just explained, definitely not.
Yup, it can take time. Don’t forget to explore the colour filters that are provided. For example, the red filter is great for enhancing skies by darkening the blue.