@OP: Why would you run Ice Breath when you have Ice Beam, which is stronger?
Myself, I was thinking of ways to use Glaceon other than the obvious Scarf/Trick Room... Then I remebered Leafeon. Why not run a Glaceon similar to Physical Wall Leafeon? Something like the following:
Glaceon w/ Leftovers + Either Nature (Snow Cloak gives you evasion hax, Ice Body helps you stall)
Bold/Calm nature (I run Bold, myself)- 252HP, 158Def, 100SpDef
Ice Beam/Ice Breath
Wish/Rest
Protect/Sleep Talk
Yawn/Toxic/Fake Tears/Charm/Roar
As a pure physical wall, Glaceon is pretty much totally outclassed by Leafeon (other than having a superior offensive type and offensive stat, but we're talking defense, here). Thus, it's better to make Glaceon a mixed wall who leans towards Physical. Ice Beam is standard to make you not taunt bait, and will still deal some nice damage though uninvested, especially to any dragons that think they can setup on you. Ice Beam is stronger, but Ice Breath deserves mention for the ability to ignore stat boosts/drops, as rare as defensive boosting is. Wish/Protect is healing and lets you Wishpass, and Rest/Sleep Talk is, well, RestTalk. For the last slot we pretty much have a list of Glaceon's support movepool. Yawn can force switches or inflict sleep, but the sleep clause diminshes it's worth somewhat. Toxic is, well, Toxic. Fake Tears can force things out- Nothing wants to take double damage from a STAB Ice Beam off 130 base Special attack, even if it is uninvested. And if they stay in, well... See Screech Flygon. Charm can work to render physical attackers completly uneffective and force a switch, but has only limited use. Roar is phasing, and could be an interesting option with RestTalk- however, a lot of pokemon do RestTalkPhase better.