As i said, i think the 2nd image is afr better, so i'll use that as an example.
I'd have 'MUTU' in the bottom left hand corner, fairly large, and the 'The GTA Place Forums' underneath, but smaller, so the whole of that text is the same width as 'mutu'
Also, just use a different font, and make the colour like, something blue / grey / black / silver or whatever, just so it looks good and fits in with the picture.
Also, use a border on every sig you do..... Just always looks better.