This is a variation of many of the other freeze mage decks. After experimenting with them I've found this combination to be very good, and my win rate has been very high.... I haven't kept up exact stats though.
I used the Otter Pops deck as my starting point, then made changes.
The end game can pan out many ways depending on your health, use of secrets, etc. you can win with or without using the legendary cards. you'll want to always play the secrets... Usually the Ice Barrier around turn 3 or 4 (depending on what minions the opponent has out) and then Ice Block afterwards. Don't focus on preventing damage to your hero until you start to get lower than about 15 health... By that time you should definitely have an ice block up, and enough freeze spells to keep from getting hit until you are able to drop Alexstrazia. I usually end up having all secrets triggered, before I make the killing blow (Not always though!) Malygos has really come in handy if the use of the Archmage doesn't pan out.
Enjoy... I have.