1) Hogwarts is Harry's 'Shire'
I have to say this though, Tolkien came up with the tale of one Horcrux being destroyed & Rowling came up with a story of seven such things being destroyed and I am glad to have had the pleasure of reading both.
2) Attention to detail: the Weasley/Black family tree vs the shire-folks' family trees
3) Who is more powerful: Dumbledore or Gandalf?
4) Who is darker: Sauron or Voldemort?
5) Aragorn-Legolas-Gimli team vs. Harry-Hermoine-Ron team.
6) Gandalf is to Frodo what Dumbledore is to Harry
7) Moria vs. the Cave on the rocks.
8) Eowyn-Aragorn vs. Hermoine-Krum
9) Aragorn's mom vs. Harry's mom.
10) Boromir vs. Marietta.
11) Fellowship of the Ring vs. Dumbledore's Army/Order of the Phoenix.
12) The Old Forest/Fangorn Forest vs. The Forbidden Forest.
13) Brego was to Aragorn what Buckbeak was to Sirius
14) flying Nazgul vs. flying Voldemort & Death eaters
15) Eagles in LoTR/Hobbit vs. Thestrals/Hippogrifs in Potter books - both helpful in battle/emergency transport.
16) Was the One Ring Sauron's Horcrux?
17) Phoenix-core wand is to Harry what Sting is to Frodo.
18) Grindelwald preceeds Voldemort as dark wizard in the potter books; Morgoth preceeds Sauron in Tolkien books - all 4 appeared to be good & turned bad later.
19) Shelob vs. Aragog.
20) Gandalf's dragon vs. Fred's & George's dragon (fireworks)?
21) 'Lights' in the Dead Marshes vs. Inferi in the Cave.
22) Pranksters: Merry & Pippin vs. Weasley Twins.
3) Who is more powerful: Dumbledore or Gandalf?
4) Who is darker: Sauron or Voldemort?
5) Aragorn-Legolas-Gimli team vs. Harry-Hermoine-Ron team.
6) Gandalf is to Frodo what Dumbledore is to Harry
7) Moria vs. the Cave on the rocks.
8) Eowyn-Aragorn vs. Hermoine-Krum
9) Aragorn's mom vs. Harry's mom.
10) Boromir vs. Marietta.
11) Fellowship of the Ring vs. Dumbledore's Army/Order of the Phoenix.
12) The Old Forest/Fangorn Forest vs. The Forbidden Forest.
13) Brego was to Aragorn what Buckbeak was to Sirius
14) flying Nazgul vs. flying Voldemort & Death eaters
15) Eagles in LoTR/Hobbit vs. Thestrals/Hippogrifs in Potter books - both helpful in battle/emergency transport.
16) Was the One Ring Sauron's Horcrux?
17) Phoenix-core wand is to Harry what Sting is to Frodo.
18) Grindelwald preceeds Voldemort as dark wizard in the potter books; Morgoth preceeds Sauron in Tolkien books - all 4 appeared to be good & turned bad later.
19) Shelob vs. Aragog.
20) Gandalf's dragon vs. Fred's & George's dragon (fireworks)?
21) 'Lights' in the Dead Marshes vs. Inferi in the Cave.
22) Pranksters: Merry & Pippin vs. Weasley Twins.
23) Round-faced & fearful: Fatty Bolger vs. Neville Longbottom.
24) Gay-couple: Legolas-Gimli vs. Dumbledore-Grindelwald.
25) Teams: Bilbo + 13 Dwarves with 3 Trolls (The Hobbit) vs. Harry + Hermoine + Ron with 1 Troll.
26) Pathetic position: Gollum or Winky
27) Better betraying the bad guy's trust: Saruman or Regulus
28) Final Battles: Before the Black Gate vs. Battle of Hogwarts
29) Prophecies: Malbeth the seer vs. the 2 Trelawney women.
30) Forced to consort with the bad guys: Wormtail Wormtongue vs. Draco.
More questions will undoubtedly occur to me - I will post them on my blog as they arise...