It's a funny thing with Rockabye Baby's Lullaby Renditions of Metallica--the disc is both all about the music and it's not. Consider it: on the one hand, here is a righteous, fully recognizable assortment of vintage Metallica tunes, including "Master of Puppets," "Enter Sandman," and "Nothing Else Matters." On the other, what's to stop a suburban massage parlor from passing it off as another generic, therapeutically new-age soundtrack to release tension by? Not a lot. The point being that this is a strangely versatile disc, but one no Metallica-loving new parent should be without. Starting, appropriately enough, at "One," producer and performer Michael Armstrong reduces Kirk Hammett's once rib-crushing riffs to xylophone and toy piano; "Fade to Black" becomes powder-puff pink, "(Anesthesia) Pulling Teeth" becomes more like "(Band-Aid) Kissing a Boo-Boo." Somewhat miraculously, what once was suitable listening for leather-wearers only becomes music to fasten Pampers by. Enjoyably. Upping the gift-appeal factor is Metallica's inarguably cool liner notes: scissors, string, tape, and a hole punch turns them into a heavy-metal mobile to hang over baby's bed. --Tammy La Gorce