automatic upgrade plugin won’t upgrade me to 2.6.1

When I try to upgrade it freezes. If I follow the first step it takes me to a blank white screen. If I follow the second choice with no back up i can get to the last step in the upgrade but when i hit “let’s go” it takes me to the white screen again, then just sits there. I’m not sure if there are other plugins that may interfere with it or if there is something wrong with my blog, it seems I get a lot of 500 server errors, especially when I try to install certain plugins, some just won’t load. One plugin that is given me the 500 server error recently was the new one click installer, it worked for a while then an upgrade with headspace 2 came up and here came the error, I found the one click installer was the problem. Some how it interfered with the headspace 2. Weird huh. I think I have gremlins. Please help with some exterminating so I can upgrade, I’m not real sure if I can do it manually.
Thanx,
Mike