I would use つまらない or つまんない instead of ひま. ひま describes free time for a person. これ、つまらないですよ。 If you want to make your expression a bit lighter you could also say 面白くない (not interesting; although Japanese people might also use 面白い to describe something that they don't like)

This is boring. これはつまらないです。 I rather say "これはあまり面白くないです". "つまらない" is direct expression like Shin said. Thus I would tell my friend "これはつまらない" if something were really boring.