I suppose what I could do instead is install the US version then use the Canadian language pack - which is almost what I do now anyway; I install the en-GB version then the Canadian spelling pack. I had assumed there were other elements of the browser that were localized for British English, which is why I installed the en-GB version.
well, there is an easy solution to that. Just use IE to update Zune TOS terms. Its not like you are going to burst into flames for using IE to complete a rarely accessed TOS page.