I take the One-A-Day Weight Smart ... NOT because I believe the extra ingredients will help in weight loss, but because it's a good basic multi formulation that is inexpensive (when on sale) and uses 100% beta carotene as the Vitamin A.
As for "losing 10 pounds as quickly as possible" ... everyone here will tell you that losing permanently, with healthy lifestyle changes, should be your true goal. The more drastic measures you undertake to lose quickly, the more likely you will be to regain the weight. The reason for this is that extreme methods are not only impossible to sustain, but often lead to rebounding into extremes in the other direction, AND often lower your metabolism.
You are smart to recognize activity is a key. What's fun? Well, what's fun for you? You may have to experiment to find activities that you find enjoyable, but walking is a great start. For variety find some parks and tromp through the woods, the more hills the better. There's also biking, swimming, rollerblading, etc. Play pick-up basketball at the rec center. Or tennis. (Or soccer??) If you want to take a class or get some videos, there's traditional aerobics, spinning, kickboxing, latin dancing, bellydancing, etc. etc. There's a whole world of activity out there, and what you will find fun may not be what I find fun. And, don't forget weight training! That's an important part of getting in shape and helping your body be the most efficient machine it can be. You are already within the healthy weight range for your height -- so at this point body fat % is more relevant to your size than weight. Strength training will add slimmer muscle while your other activities burn off bulkier fat, thus making you leaner (not to mention more fit!).
The other side of the weight loss coin is food. It's crucial not to starve yourself in order to lose quickly -- that will rebound on you in a big way. Never eat less than 1200 calories, and make sure it's well-balanced. You may even need more if you become very active. You can use
www.fitday.com to track your intake if you like; they also have some good general nutrition info.