Metallica was a gateway metal band for me and when 13 would just spin their 80's albums all the time on my 3 disk changer because I did not have many cds. I do not listen to them much now, but when do it's usually just kill 'em all with some beers. I feel kill 'em has their best production songs and is their most aggressive album(the guitar picking is massive). Kill 'em all is the most fun and enjoyable album from metallica nor drags out.