Out of the 75 eligible entries I received, 26 had all five questions answered correctly. 34 entries had a single incorrect answer, 13 had two incorrect answers, and 2 had everything wrong. The one entry with the Eggman symbol is the entry I disqualified due to massive spamming from a single user.
Now, onto the questions!
Question #1: What was the original name of the Sonic Retro Wiki?
There are actually two valid answers to this question: SSonicNET Database and Sonic the Hedgehog Information Treasury (aka SHIT). I accepted both answers, as well as entries that contained both answers and a couple variants of SHIT. This was a fairly easy question; it's right there on the wiki page for Sonic Retro. ("Both Answers" indicates an entry contained both "SSonicNet Database" and "SHIT", which I will accept.)
Question #2: What was the first official Sonic game released for a non-Sega platform (excluding PC and single-game handhelds)?
"Single-game handhelds" here was referring to things like Tiger LCD games that could only run a single hard-coded game, whereas systems like the Neo Geo Pocket Color accept removable cartridges.
This question tripped up a lot of people. I received many entries with "Sonic Advance" or "Sonic Adventure 2: Battle". These were the first Sonic games available on Nintendo platforms (released on the same day in 2001 in Japan), but not the first on a non-Sega platform. "Sonic Pocket Adventure" for the Neo Geo Pocket Color was a better answer (1998), but still not the first. The correct answer here is "Sonic Jam" for the ill-fated game.com, which was released in 1997.
Sidenote: Three Sonic arcade games were mentioned in the entries. "SegaSonic the Hedgehog" runs on Sega's System 32 hardware, and "Waku Waku Sonic Patrol Car" and "SegaSonic Cosmo Fighter" both run on variants of Sega's System C-2. These are both Sega platforms, so they are incorrect.
Question #3: What celebrity got the chance to play a Sonic 2 prototype on the TV game show Nick Arcade?
Pretty much everyone got this one right: it was Melissa Joan Hart, who was the lead role in "Clarissa Explains It All" at the time. She appeared in a special celebrity episode of Nick Arcade, which featured all four members of the Darling family.
Question #4: What Sonic 1 zone was originally going to follow Green Hill Zone, until the developers decided it would be too difficult as the second zone?
Another easy one, especially considering a remnant of this choice can still be found in Sonic 1 rev00's level select. It's Labyrinth Zone.
Question #5: Big the Cat is known for his cameo appearances in Sonic Adventure 2. What other Sonic game did Big make cameo appearances in?
I had a specific answer in mind for this question, but it turns out Big makes cameos everywhere. The game I was going for was "Sonic and the Secret Rings", which has an entire Special Book section dedicated to Big's appearances; however, I will accept any game in which Big has a cameo appearance (I.e. isn't playable and/or doesn't have an important role in the storyline). (The "Multiple" entry in the chart indicates entries that contained multiple games; I'm accepting this as correct.)
I will most likely hold the drawing for the winners sometime this weekend. Stay tuned for more information!