President Bush is a dipshit of the highest order. He's ruining our country from both at home and abroad. But unless we find a truly smoking gun, there's not a good way to go about it.
I do wish we have a system that had a "no confidence" clause for situations like this, where there was a way to force a new election if the president hasn't necessarily committed a crime, but is just doing a terrible job. This would at least give the president a motivation to represent the people who elected him, especially in their second term.