1) Dragon 391.
2) It might be a little bit unfair. I certainly wouldn't give it both high crit and reach. Out of curiosity, why do you want all of these combinations?
A479
First, I presume you're referring to Power of the Storm, since as far as I know there's no game element that's "Power of Storm."
Beyond that:
1) Only one Shard per weapon.
2) Power of the Storm and Frost Weapon both overwrite all damage to their type, so in turn, the power is either Cold or Thunder, but never both. This is true of most of the damage type weapons; it's a part of why high-op folks are fans of Genasi (who have the ability to get fire and lightning added to powers) and Frozen Whetstones (to add cold damage). Also why Malec-Keth Janissary occasionally gets suggested as a Paragon Path for random characters (+1d4 element type damage).