I would recommend to someone completely new to the metal world something of a soft nature. Keep a new person completely away from anything too harsh, like growls and screams and extreme power chords and double thumpers.
I have to respectfully disagree with this. I do understand your point, but while one person new to metal might only want to hear more gentle stuff, others might want to hear stuff from the opposite end of the spectrum, or not even know what they want to hear until they do hear it.
I once recieved a compilation tape containing songs from Dimmu Borgir and Arch Enemy, and the harsh vocals and extremely fast drumming completely blew me away; I went out and bought both band's entire discographies on the strength of the songs I heard on the tape. But at the same time, I also collected the discographies of lighter, more gentle bands featured, so to me, it was the best of both worlds.
Whenever I make a metal compilation for someone, I try and vary it as much as I can; harsh and clean vocals, male and female vocals, gentle melodies and fast chugging riffs. This gives someone new to the genre a bigger selection to choose from, thus increasing the likelihood of them finding something on there that they like. Some stuff obviously goes down better than others, but that depends entirely on the individual the compilation is being presented to. If you make such a varied compilation and present it to ten different people, you can guarantee that no two of those people will like the exact same songs or even dislike the exact same songs. We are all different, and this can only be a good thing
