I'll preface my comment with a disclaimer: no, I don't play guitar. I don't, by any means, consider myself even remotely a connoisseur of what is "great" music, and my exposure to music is limited to what's generally on the radio. So, if my tastes seem blasphemous to some, I am here to offer my views as a layperson. End disclaimer.
That being said,
Sweet Child O' Mine is probably one of my favorite songs, with one of the most readily recognizable guitar riffs right at the beginning. You can't mistake it for any other. I agree with ILikePie: there's something uplifting and free about it. Ironically, supposedly Slash didn't even like the song much (per
Wikipedia, citation not verified; I can kinda see the first riff being a little simplistic, but the middle solo is sweet).