When I google "myxboxspot" my domain is 6th on google. My domain name is MyXBOXSpot.com before the PR update I was the top when I googled it. How can I improve it, Is it because my page rank is only a 1. and the other sites are higher?
Pretty much. That is why when I offer a site for sale here (dp ranks high) I always do it with an image file or a distorted domamain dot com name. You can also kill your your key words in the same manner if you you use them as anchor text on a better rated site.
Really to get the ranking back, it will mostly come down to getting more backlinks. I am really surprised you said that. That goes against most seo strategies. You definitely want to get links from higher ranked websites using your target keywords as anchor text. You would have to a pretty weak site/page to have its rankings lost to a page that merely mentions your keyword in an outgoing link.
google thinks other sites are more important than yours for the search term. Get more backlinks, and put more unique content on the site.
Page rank and ranking both are different things try to improve your back links and concentrate on your site