For an interesting and informative take on the topic, take a look at this link to a page on an audio enthusiast's website where he very neatly outlines his own thoughts and processes behind cleaning records and the methods he supports. It's an excellent and informative read, regardless of your decision to adopt his methods.
http://www.indiespinzone.com/other/recordcare.html
http://www.indiespinzone.com/other/recordcare.html