to get rid of the security warning when you open a chat window go to
right click on messenger:
show package contents>contents>resources>(your language).lproj and find InstantMessageWindow.strings>open it with textedit or similar and at the bottom of the file you can leave yourself any message you want
my question is how do you get rid of the msn icon next to your chosen text?!

Thanks for that looking for it myself.
What MSN icon do you mean (screenshot?)?
O thanks just figured that one out b4 u replied 
But now, theres this thick ugly grey line (~3 pixels) where the tabs were. I cant stop staring at it 

Yup. You're right, it should be only 1 pixel thick.