Does Resist 1 all such as is profiled by Rimefire Plate +2 prevent normal / untyped damage, such as is done by an axe or arrow?
Resist 1 all allows you to prevent 1 damage from any source.
This is clarified, albeit obliquely in the official FAQ.
Unfortunately, the rules are unclear about what "Resist All" means.
At the very least though we can assume that Resist All reduces damage from all attack types, including normal and untyped damage.
What is less clear: Does "Resist All" mean "resist everything" or "resist all damage" or "resist all damage types"?
Resist Everything: This implies that any attack's damage is reduced by 1 and the character has resistance against everything for purposes of determining non-damage effects. If an attack deals 4 radiant fire damage, the resistance would reduce that to 3 radiant fire damage.
Resist All Damage: This implies that any attack's damage is reduced by 1. The character does not have generic resistance against all effects though. The damage would be handled as above. The D&D 4E FAQ indirectly addresses this case (referring to "resist 1 to all damage"):
28. Do resistances stack?
You use your highest applicable resistance when you take damage. For instance, if you have both resist 5 fire and resist 1 to all damage, you have resist 5 against fire damage and resist 1 against all other damage. You do not have resist 6 against fire damage.
Resist All Damage Types: This implies that any attack's damage is reduced by 1 per type. Imagine it says "Resist Cold AND Resist Fire AND Resist Poison..." If an attack deals 4 radiant fire damage, you have resistance to both radiant and fire damage, so you would reduce that to 3 radiant fire damage (or maybe 2 radiant fire damage, depending on how you interpret it). Furthermore, the character has resistance to all damage types for purposes of determining non-damage effects.
If you believe "Resist All" means "Resist All Damage Types" (#3), then you must decide whether "all damage types" includes untyped/normal damage. The rules do not specify that untyped damage is really a type of damage. Each DM will have to decide if this is the case. If untyped is a damage type, then "Resist All Damage Types" should reduce untyped damage; otherwise, it should not. The rules (and logic) are stacked against untyped damage being a type of damage, however.
Some people believe that the Adamantine Weapon magic item provides evidence that Resist All applies to untyped damage. If this is the case, then the "Resist All Damage Types" interpretation probably isn't true. The item description reads:
Untyped damage done with this weapon ignores a number of points of resistance equal to twice the weapon’s enhancement bonus.DDI
Also, if your "Resist All" is described as Variable Resistance, then the rules will be different. Variable resistance reduces one type of damage at a time until changed, and activating it is usually a free action that can be done a certain number of times per encounter.
If "Resist All" means "Resist All Damage Types," then it probably doesn't reduce normal / untyped damage, because that's not a type. More likely, "Resist All" means "Resist Everything" or "Resist All Damage." This means that it reduces the damage and may or may not include generic resistance against all other effects.