How to change PCMan for Thunar??

[demonboy]

I am Brazilian, I can not write in English, so pardon if it is hard to understand because I used google translator.

Not like the window manager lxde because it has thumbnails of PDF and videos, then installed thunar but I do not adjust it to be the principal manager. I tried deleting the PCMan, but then disappeared all icons from the desktop, i had to reinstall it. I want to become the manager thunar main help me ...

[demonboy]

Another thing guys, when reinstalled PCMan, now the files are no longer recognized by their proper programs. For example a pdf file, its icon is undefined, as if he had not evince scheduled to open it.

Forgot: I'm using linux mint 8, lxde