Hi
We are unable to replicate your issue regarding the horizontal scrolling. We have checked on IE, Chrome and Firefox.
Regarding the logo try adding the following to the Custom CSS field of your templates parameters...
[code type=css]h1.logo a {
background-size: 100% auto;
}[/code]
Note you will have to crop all the white space from your logo first (
http://www.mathmotionmontreal.ca/images/logo.png). If you are using an older browser this may also fix your horizontal scrolling issue.
Ciaran