Need someone to handle wordpress problems

Hi, I can't use plugin thing in WP. When I go to plugins in my dashboard I get this error - Fatal error: Cannot use object of type DTCCache as array in /home/theymen/public_html/haircareetc/wp-includes/[login to view URL] on line 799 If it could be solved directly good, else I need someone to backup my wp blog and then upgrade it - may be then the problem is solved. Else I want someone to do this simple thing doing which I won't need a plugin - As The theme header reads like this - <title><?php bloginfo('name'); ?><?php wp_title(); ?></title> Can it be changed to this - if it is the home page or just a page, it should be - <title><?php bloginfo('name'); ?></title> And if it is a post - it should be - <title><?php wp_title(); ?></title> Hope someone can help me.