[SixOfSpades]

Actually, Narsil was of Dwarven make: "Telchar wrought it in the deeps of time." Telchar was always described as living in Norgrod, so Narsil dates from sometime from the latter half of the Ages of Stars, to the end of the First Age of the Sun. How it became an heirloom of Men is, I believe, unrecorded. Looking in my Tolkien Encyclopedia, I see that Telchar also made Angrist, the knife that Beren used to cut the Silmaril from the Iron Crown. So it would appear that Telchar's specialty is creating blades that can pierce strongly-enchanted creations of the Enemy.

Orcrist, Glamdring, and Sting were all forged in Gondolin, and should glow. Narsil/Anduril are never described as glowing.

Narsil/Anduril: Can cut pretty much anything, probable combat bonuses vs. Evil. A weapon made by Dwarves would not be restricted to a class that Dwarves cannot be, so a pure Alignment restriction would be more appropriate. Size capped at Bastard Sword, since a Dwarf swinging what would be a Two-Hander on a Human would just look ridiculous, especially in a cave.

Orcrist: The "Goblin-Cleaver." Substantial combat bonuses vs. Orcs & Half-Orcs. Likely a Long Sword, as Elves favored that size. Glows when around Orcs, although described as glowing around any enemy after being placed on Thorin's tomb.

Glamdring: The "Foe-Hammer." Magically added Blunt damage to each hit, apparently, or perhaps was just as deadly when using the flat of the weapon instead of the blade. Again, likely a Longsword.

Sting: Apparently forged as a specialty weapon when journeying in Ered Gorgoroth. Provided substantial bonuses vs. Spiders and perhaps such things as resistance to such things as Poison and Webs as well. Short sword.