Hi Favored13,
Thanks for writing. I am sorry to hear that you are having trouble getting the weight off, and know that it can be frustrating, but stay committed and you should see positive results.
Adding strength training into your weekly regimen 2-3 times per week, for about 25-35 minutes each session is very important and will help you become more metabolically efficient. By maintaining/increasing lean muscle you will burn more calories all throughout the day, even at rest, because muscle requires more energy than fat. Replacing fat with lean muscle is very important, and strength training is the way to get there!
Mixing cardio and weights on the same day is not a BAD thing to do, in and of itself. If you need to do that for time sake, the ideal thing to do is to perform your ST first, and then cardio. This way, you ensure that your muscles are fresh and can safely perform the ST exercises effectively and not be already fatigued by doing cardio first. Another idea is to do them separately during the course of one day. Perform one in the early part of the day, and then the other at least 4-6 hours later. Pilates, yoga or any other type of exercises can definitely be performed on the same day as you walk. I would however, make sure that you're not performing ST on every day of the week as your muscles need adequate time to repair and recover.
It would be a great idea to begin to include a variety of exercises into your week. Try some exercise DVD at home, such as Taebo, The Firm, Yoga Booty Ballet, or Leslie S.'s walking videos. Go for a hike or bike ride, join a Boot Camp or take a dance class. By consistently challenging yourself, you'll stay motivated and begin to see a real difference in your body! Keep those muscles guessing!
Keep your chin up and stay positive! Remember that the scale is only 1 barometer of your success! Unless your scale has a specialized feature that reads % body fat, you're only getting 1/2 of the picture. Losing inches and body fat is just as, if not more important than the # on the scale going down!
Best in fitness to you and good luck,
Kelli