I accidentally dragged a picture to my msn convo windo and it turned a horrible red colour , too confusing to read the text, i know how to change background images but when i set it back to white, it had a subtle yellow tint to the top bar of messenger, also msn itself , not the convo window but msn main window is red, and i have no clue how to make that a normal colour again, please someone help!

I'm assuming you're on WLM.

On the contact list, there should be an icon of a paintbrush on a bar just below your dp, name, pm etc. click it and choose the colour of your choice. It should also apply a lighter shade of that colour to the convo window, but you can change that too, with the same icon in the convo  window

it aint possible... when i choose the default blank background it still looks red... and if i choose an all blue background it turns blue but the top bar of my convo window remains red.

First open the problematic conversation window and then do as said in the picture...



Edit: Can you post a screenshot of your window please?