Using trademarks in a domain name opens the door for having the domain taken or having a lawsuit filed against you. You can't use a mark owned by someone else to ride their goodwill unless you have their permission. Both the above are registered trademarks. Microsoft in particular is known to be aggressive.
Ah okay. Well I just noticed that if you do a google search it seems like there are lots of "xbox360" domain names. I came across one that could be profitable but thanks for clearing that up. Would "windows" be a trademark? Because "browser windows" is a name for internet browsers so i thought that one could pass as long as the content of the site doesn't relate to windows operating systems and such.
When it comes to generic words, usage determines infringement - so while a trademark holder can sue anyone they "think" is infringing upon their mark, your chances are greatly reduced if the usage has nothing to do with their usage/product. It would be a huge mistake to assume that if someone else is doing something on the net it must be ok.
You might still be able to get the domain name if you email the companies and ask them, you might be lucky.