I used to think the Dexys Midnight Runners song "Come on Eileen" was "Mohamed Ali" and I always wondered why they sang about it but I couldn't find out because I didn't know the title or who the band was...
So I just added it on my itunes as "Mohamed Ali" by "Watchamacallit" until I saw the show "100 greatest 1 hit wonders", I was so happy to finally find out what they were saying.
A childhood belief about misheard lyrics

others believed things like this
- for my little sis -
Paul McCarty song "Band on the Run" but when she sang it it was "Man has the Runs"Anon - For the longest time I didn't know that Spinal Tap wasn't a real group. No wonder I couldn't find their music.— Louis
- I used to think that the actors on tv shows sang the show's theme song.Anon
- I used to believe that when I went to the mountain I would find an ancient monster or find some treasure— Yazer Solorzano
- Even though the title is 'How Bizarre', I always thought he sang "help is on"...Anon
- Until I was about 15, I beleived my Father was the person who sang the "Cheers" TV Show Theme Song.— Dustin