The only error I can see in this sentence is roll-a-coaster. I believe it should be a roller coaster instead, which is a ride in amusement parks. Other than that, it is more grammatically correct to say "I've just gotten off the wooden" rather than "I just got off the wooden" however, it's up to you.
Books that are surrounded by oxygen will turn yellow, so basically, all books since oxygen is constantly surrounding us. Oxygen-rich conditions are very bad for paper, which gives them the yellow tiny. This is actually called lignin oxidation! Lignin oxidation gives it a yellow or brown colour as you said. Yellow comes first, then brown after.
I hope this helped a bit! :)
The metaphor for life in this poem is a game of Monopoly with no winner. The poem describes a situation in which, through the process of trying to beat out the other competitors in the game, no player ultimately wins (see the "Crabs in a Bucket" metaphor for a similar idea).