Is there a way to figure out what the scope of each of these access rights are to the folders?
I'm not sure what you are asking. Each assigned right should have its scope visible in the dialog.
So where i'm confused is, what's the difference between "folder and subfolders" vs "folders & its immediate children" - i would assume that's the same. is there some sample or documentation somewhere that shows an example of each of these rights?
The documentation has a chart that should be helpful: https://doc.laserfiche.com/laserfiche.documentation/en-us/Content/Access_Rights.htm. The main differences between the scopes are the types of entries that are included and how far down the rule applies. In your case, "folders & its immediate children" includes documents, which are not covered by "folder and subfolders". Also, "subfolders" means that the rule continues to apply down the tree.