Which English to use? 

Hi!  I saw your comment on Scientizzle's talk page, but since he's on wikibreak I thought I'd step in.  You can read the official policy at WP:ENGVAR.  If an article has a strong connection to a particular country (e.g., Harry Potter, Abraham Lincoln), the spelling should reflect that country's standards.  There are other rules, of course, but the most important this is not to change a word just because you spell it differently.  If the article uses "colour" throughout, it should stay "colour".  You can, however, change words to make the spelling consistent throughout the articlefor instance, if it's spelled "manoeuvre" in the first and third paragraphs but "manuever" in the second.  

If you have any other questions, feel free to ask!  You can also put  on your user talk page along with your question, and a friendly editor will be by soon to help out.  And don't forget to sign your posts using ~~~~!  Cheers!