Looking for class, subtlety, good acting, thought-provoking substance...? This is definitely not the movie to watch.
Once you get past the tongue-in-cheek killer-snowman references and obviously unskillful cast, you'll be able to enjoy the sheer depravity of the humour here. That is, if you've got an appreciation of the macabre and campy.
I usually don't subscribe to the theory that bad is good. In this case, however, the director obviously knows his filmic comedy -- his reveals are startling, the concepts quite original, and the execution pretty nifty. The striptease montage, for example, ends on a very satisfyingly coy note (great use of sound effects and music here), as does the rocking-chair gag. The malignant-snowman concept bears much potential for creative gags and Cooney milks it effectively.
Walk in expecting cranial matter and you'll obviously be disappointed. As silly, black film comedy, however, Jack Frost is highly enjoyable. One note, however -- unless you're the horror-unsavvy kind that gets scared at I Still Know What You Did Last Summer or Scream, don't expect any horror out of this one at all. Texas Chainsaw Massacre this isn't.