Thanks for replies and information longtom & Sproggy.
Today when I opened PCManFm in Xfce it automatically mounted my other partitions. Funny it didn't do that yesterday.
Anyway, then Thunar showed them as well under /media.
I didn't see a big increase in memory usage using PCManFM. I don't have a good understanding of the kde dependencies and which non-Xfce programs to avoid using.
Sproggy, I'm reluctant to change fstab because I want to keep my other partitions unmounted and only mount them only as needed. Would changing fstab mount them automatically? I may be wrong but I feel that gives them added protection.
Another question using Thunar, is there a way to open a file or folder as root?