A resume is not meant to be your life story. You do not have to bare your soul and share every ugly detail of your work history. Your resume is your personal sales brochure whose only purpose is to get you an interview. To help show yourself in best possible light, carefully choose what you put on and leave off of your resume.
You should (almost) never include following:
1. Dates that reveal your age. Sad to say, but age discrimination is alive and well. Ways to avoid revealing your age include not showing year you graduated from college and not listing all of your work experience (only include most recent years that are most applicable to position you are applying for). If you are applying for a position that requires many years of experience, then your age may be an asset, otherwise don't take that chance.
2. Hobbies. Unless your hobby is directly related to your career, it's best to leave it off. Showing too many activities can cause employer to worry if they will interfere with your work. In addition, space used for discussing your hobbies could be better spent on discussing your skills. The interview may provide you with an opportunity to talk about your hobbies as it provides you with an opportunity to show how well rounded you are.
3. "References available upon request." This is a waste of space. Most often when you fill out job application there will be a place for you to list your references. Use space on your resume to discuss job specific information.
4. Generic objectives. Objectives like "To obtain a challenging position in a fortune 500 company" don't say anything. Your objective statement should be custom tailored to position and company you are applying for. You can also replace your objective statement with a skills summary or professional summary if you think that will better serve you.
5. Short lived jobs. Employers don't like job hoppers. Most employers want to believe that their employees will be around long enough for them to recoup dollars spent on training. Leave off any jobs that you only worked at for a few months. If you worked several jobs with a temporary or contracting agency, list agency as your employer and each job as a project or assignment. Of course when it comes time to fill out job application list all of your employers even short ones; but by then hopefully you'll already have an interview scheduled where you can then address any concerns or issues.
6. GPA. Once you are more than a couple of years out of college, your GPA becomes fairly irrelevant. The only exception to this may be careers where there is heavy emphasis placed on education; in that case it may do you good to include your GPA or class ranking. But even in those situations, if your GPA was average or low, don't draw attention to that fact by listing it.