Wow, lovely work.
Where did you get the wonderful lighting...errr maybe don't answer that as it's likely something I haven't "done" yet in game.
As far as uploading goes
I created an Imgur account, then used ... word or paint - I forget which - to edit my screenshots, uploaded them and then used the BBC code messages and forums option pasted into posts here.
Here is an example. On the left is my character Zyl Banefire, half drow Trickster Cleric of Selune; whose attention is on calculating the best way through this mess. On the right is Dierni Kismet (Kiss), who is planning the most efficient route to kill/loot and generally gain all the advantages (and treasure).