Correct my (X)HTML & CSS to make it W3C compliant

I require my web coding corrected to make it W3C compliant. The URL is http://www.360hdtours.co.uk and the CSS Validation Service is currently reporting back 23 errors and 170 warnings. The website was designed from a purchased template, so I have the basic knowledge, but the error codes are beyond me. The job would require the correction of the css file and advise on HTML corrections as I may be able to do these myself in dreamweaver. PDF of WC3 report attached.