"I would produce a nice and tight 30 second commercial for yourself showing a montage of your work. Let this sequence play out and take you to a DVD menu with seperate links to individual pieces of work. It's a bit of work but i always think it is worth tailoring your CV and Reel for each job you are applying for." - PJT
I have to agree with PJ's recommendation. Tight, snappy, nicely edited montage of cherry-picked shots from your work as the intro. DVD menu with chapters leading to some of your individual stuff.
I would only add, START with your BEST stuff, don't "build" up to it. Your best stuff is the ONLY stuff that has any hope of keeping their attention for any length of time. I also agree with another poster who suggested an over-all length of not more than five minutes. Believe me, they ARE NOT going to watch it all unless you prove in the first 10 seconds that you are the new god of video production.
Quality work, with NO gimmicks (often stuff used to cover production mistakes - strobing comes to mind for covering up unstable camera shots) and quality audio - TIGHT EDITING works.
Ultra intense or complex composite sequences can and do wow people on both sides of the screen, but you have to realize (well, it has been my experience anyway) that unless you are going to become the station's grapics production person and will be required to pull off some major network looks, most local stations and cable companies are looking for someone who can produce some basic popout stuff - think auto, electronics, mattress "...will beat anyone's price or YOUR MATTRESS IS FREE!" and related spot ads for example.