Gollum would wear a dark blonde wig, a glove on his right hand, and carry a blue lightsaber, and Frodo would part his mullet on the side, grow a beard, and likewise carry a blue lightsaber. Then the two of them would proceed to Mount Doom where they would battle to the death and Frodo would cut Gollum's appendages off and throw him into the lava. (Sauron would show up later in a raggedy black robe...)
Meanwhile, back in the Shire, Sam would wear a white porcelain mask and teach Rosie how to sing from underneath the bar...
None of that was really Halloween but I'm in parody mode today.