How to upload a picture to this club as a regular size photo?

It just depends on the size of the image. Whatever the size of the image that's where it's going to go. You just need to check the size of the image. Here's some ex:
Images 250px by 250px or smaller will go to icons.
Images: 1000px by 1000px or larger will go to wallpaper. Images 400px by 400px or larger go to photos or fanart (but that's by choice)

Hope that helps :)