Designer - CSS Expert for Design- Review and Bugfixing

Our Website [[login to view URL]][1] needs some review and Bugfixing on the Design. General design review of the existing layout: -- I am quite satisfied with the design, but i am not an expert: -- At first, the design should be professional, trustworthy and pure and therefore usable -- What could be a large improvement with small effort? -- What is worse Then implementation: -- Results of the review should be implemented -- Known errors to fix: - IE 7 + 8 display errors of the top menus Sidebar menu items to far right, and thus resulting in Line-breaks and display errors in IE, Mozilla -- -- Sidebar does not look professional, but it should - so it needs work