I love Kundalini. I did one of Ravi/Ana's dvds about 4 years ago - I started with Yoga Beauty Body - and was immediately hooked. I now own all of their dvds (about 15 - 20 I think) and have bought every other Kundalini dvd on the market, most of which I still have.
Kundalini is not at all like vinyasa flow yoga. It is more geared toward working on the chakra systems and keeping the glandular system healthy and in balance. A typical pose might be: sit cross legged; hold your arms out to your sides, bent at the elbows like goal posts, forming a right angle. Twist rapidly to the left and right, doing a very fast breath called "breath of fire", fast light breathing through the nose - carry on for about 2 minutes. OR, squat with your hands on the floor in front of you for balance. Stand up, bending at the waist, so that your legs are straight and your head is down. Then return to a squat, then up and down etc. for a minute or 2. The poses are often accompanied by rapid breathing or by very slow deep breathing. The practice is usually done with the eyes closed, you are supposed to focus on the "third eye" point in the middle of the forehead.
The exercises can be physically tiring and I have found (and have read that others have found) that they can be emotionally freeing - I have had emotional releases during some poses, started crying for no apparent reason, suddenly felt like a burden had been lifted from my shoulders (figuratively speaking) - not super dramatic reactions but definitely noticeable.
There is some chanting (in Sanskrit I think it is?) sometimes in the final meditations, and a "tune in" and "tune out" portion with a one-sentence chant at the beginning and end of all the practices- my woo-woo tolerance is not high and yet I just go along with all of it and it doesn't bother me, but if anything new-agey bothers you you might not like that part of it.
I notice a dramatic difference when I am doing kundalini regularly (twice a week or more) vs. when I don't - I look more radiant, I have more energy, my moods are better, I feel much happier and healthier, my appetite seems to regulate itself, I sleep better, I'm more tolerant of other's foibles, etc. I have gone through several periods where I didn't do kundalini for awhile and noticed a huge difference after picking it up again, even after doing 1 session.
If you want to get a feel for it, you could start with any of the following, which are my favorites and I think would be good for novices:
Ravi/Ana: Yoga Beauty Body (ALL TIME FAVORITE! - I would start with this one) , A.M. - P.M. Yoga, any of the Fat-Free Yogas - actually all of the Ravi/Anas are great. They do have a Kundalini Yoga For Beginners and Beyond but I'm not as crazy about that one. These are sort of glamorous, very pretty productions, which I like.
Maya Fiennes - Kundalini Yoga to Detox and Destress - she is also wonderful and also has a series of 7 dvds, one for each Chakra. Again, very good production, pretty to look at, very good instruction.
Peace of Mind in Stressful Times, put out by Kundalini Yoga East in New York (Sat Jivan Singh Khalsa). This is a wonderful practice with 4 separate stress-beating meditations, and he's a veyr good, low-key teacher, but he is turbaned and robed which might be offputting to some.
Either of the Kundalini Yoga dvds put out by Mantra Girl - but these are challenging! These are a bit Hollywoodish but I love both of them.
Have fun if you decide to explore these!