The folders icon is the middle menu item on my screen- however I'm using a modified firmware that presents all menu items in a straight line. Perhaps that would a helpful modification for your son to do for you. All he would need is a clean microcard of 32gb or smaller, formatted in your X5 first. Then just load the firmware file on the card, insert the card in slot one (I remove both cards just to be safe) while the device is off, and start it while holding down Power and the upper left button. It will tell you it has found the file, and will then update. After it does, remove the card, reset your preferences (running Factory Defaults first), and then reinsert your music cards. Then have it rescan your Library.
It's called Simply Straight, and can be found here: http://www.head-fi.org/t/717947/fiio-x5-custom-modded-firmwares/345#post_10967258
It is exactly the same as the 2.2 firmware that is the current latest release except that the menu is straight across instead of on the right side in a vertical line. I find it much easier to navigate, and I'm sighted.
Folder is the middle of the seven menu items. They go, from left, EQ, Music Settings, Settings, Folders, Album/Artist/Genre, Favorites (heart), and Now Playing (music note).
HOWEVER, there is an extra step to using Folders, as you have to choose which memory card (up to two) to access, or OTG (on the go, for an external hd). I would suggest that it might be easier for you to continue as you have been, using the Artist/Album menu, and just be careful to lock the device so there are no inadvertent clicks to throw you into wherever you went last time.
Oh, and as Huey said, "Every man a king."