I use the 1, 1, 1, 1 method for my campaigns, only because it's simple and easy to use when tracking distance of movement. I prefer the more realistic 1, 2, 1, 2, but don't like bogging my game down more than necessary. I normally play movement and facing kinda fast and loose to begin with, just so everyone at the table has a good rough idea of who, what and where.
I only use squares for indoor movement, hexes get used for outdoor movement. I'll admit that hexes are better for facing purposes over squares, if i wanna worry that much about it.
I don't use the standard 5x5 square. My squares represent 1 meter, just big enough to account for a person and their gear (hexes are 5 meters across from side to side). I'm a bit old school when looking at maps and think of 1 square equals ten feet (unless otherwise noted), I get 9 squares per one square when interpreting a map this way (or 3 per side). It's also easy to convert that meter into a yard, either way it makes drawing out a more realistically dimensioned sized space much easier (it's a helluva lot easier breaking up that 1" grid into thirds than fifths). The only drawback to this scale is the need for multiple mats to adequately represent large rooms/chambers/area's all at once.
For circular area spell effects, I've modified a compass to fit various marking implements, and actually draw the area of effect out to see who or what get's hit as necessary. I think I may snag Zinovia's scaled template idea, don't know why I didn't think of this before.
