tamara,

first of all, congrats on your running progress!

although i understand that you can feel like walking is "giving up" it is actually a very common training technique. jeff galloway has written a lot of the run/walk method and i know plenty of people that have used his training program to get through their first marathon. here is his web site:
http://www.jeffgalloway.com/

i just bought my niece a couple of his books because she is starting her fitness program from couch potato status. it is working beautifully for her. on the opposite end of the spectrum i have a close friend who did his first Hawaii Ironman last year and he also used the run/walk method to make it through the marathon portion of that event.

as for training with heart rate monitors, check out this web site for a good "starter" article on HRM training:
http://www.runnersworld.com/article/...0-1046,00.html

i don't use my HRM as effectively as i could in training but i do pay close attention to that resting heart rate and find that it is a very good measure of my readiness to train hard.

you must take the automagic calculations of your target heart rate zones based on your age with a grain of salt. my heart rate is about 10 beats faster than it "should" be according to my advanced age of 44. just use the calculations as starting points and pay close attention to how you feel in different heart rate zones.

keep up the good work!

traveller