Trouble after update to the latest release

Hi,

I updated a wordpress blog that i have with a friend to the latest release, and since then i’m running through some problems, i tried to fix it but with no luck, my friend the founder of the site, did a reinstall and fixed some other issues.
The first problem is when i try to get to my blog using this address http://ready4poker.net it doesn’t retrieve anything just a blank page, if i access using “www” before the domain like this http://www.ready4poker.net the blog turns ok. I don’t know how to fix this, do i have to configure something on the server?

The second problem is that i can’t even login to admin account, when i insert all the credentials on the wp-login.php page the page turn blank and i’m unable to do anything, my friend was able to get to the dashboard, connecting to the server using ftp and then he changed the name of plugins folder, logged in and then he renamed that folder again, he was able to deactivate some plugins to find if the problem was some incompatible plugin, but the problem persists, he doesn’t have time to continue to figure out the problem this week, so he explained me the things that i wrote and asked me to try to solve it as soon as possible.

Another thing (this is not critical, it’s just an improvement that i’m seeking) is that if a user click the adsense ads that are on the blog they leave the site, is it possible to force the ad open on another tab or window?

I will continue to try to find and solve the problem, but i’m not very skilled in this matters, I would be very grateful if someone helps me.

Thank you for taking time helping other people,
Royal_Flush
Ready4poker.net