Here are three things that, judging from my mail, hiring managers dislike in a resume.
1. Spelling and grammatical errors. We've covered this area quite a bit on TechRepublic. (See 10 flagrant grammar mistakes that make you look stupid) Some members have blasted us for our seeming exaggeration of the effect these kinds of errors can have. While I'll concede that you may be able to get away with them in the informality of day-to-day work life, you CANNOT get away with them in your resume. If you can't even make error-free a document that is supposed to, in one or two pages, present you to the world in your best light, then you've got problems. Mistakes in a resume speak volumes to a prospective employer about your attention to detail, or lack thereof.
2. Interests and hobbies. I don't know where the idea of listing your interests and hobbies on a resume originated. Maybe it was someone's attempt to present himself as a "well-rounded person." But a resume is not the place to do that. You can cover that territory in the interview.
First of all, as a manager, if I'm looking for someone who has a proven track record of managing successful IT projects, I don't much care that you do Civil War reenactments in your spare time. It's not germane and it's also a little smug. ("Look how eccentric I am!")
And what if big game hunting is your passion and I'm a vegetarian? You can't anticipate anyone's prejudices, so why take the chance?
3. Cutesy gimmicks. Before you send me all your arguments that resume gimmicks like purple paper or pop-up graphics get a candidate noticed, let me point something out. The Wall Street Journal is probably one of the most visually unappealing publications in the history of the world. But it's also one of the most respected. Why? Because the lack of screaming visual gimmicks implies that the content has some gravity. If you send me a neon resume that plays the theme from Star Wars when I open it, I'm going to think you are disguising your lack of qualifications with tips you picked up from P. T. Barnum.