SinGear,

No problem with a C25 (75%Argon,25%CO2) being stored/used at 22 degrees.

I would think that a CO2 bottle would be alright also, but, since it's a liquid under pressure, I wouldn't go any more than that.

Most gasses (O2, Hydrogen, Helium) can be stored at an angle.

You do not want to lay an acetylene bottle on it's side since it contains acetone.

Propane also should be stored/used upright since it's in liquid form.