I successfully lost 30 pounds a few years back by watching my carbs. I learned that certain carbs dont count against you because they are from sugar alcohol or involve dietary fiber...

I was buying some low carb foods, and continue to buy low carb pasta, which has more than 40 total carbs per serving, but because most of those are not digested the same way, it only have 5 net carbs.

for the sake of running and increasing my carb intake as I carbo load, is a carb a carb no matter what its form, or is the pasta or other foods that have 40 carbs but only 5 net carbs not giving me the carbs I need?

Think of it this way. If the fiber is running all the way through to the toilet, how can you get energy from it? If it says 5 net carbs, your energy from it will be 5 carbs, or 20 calories.

Complex carbs are better than sugars.

Complex carbs can have different Glycemic Index (GI). Usually, the higher on the scale, the faster the carbs will be absorbed into the bloodstream. This is bad before exercise because it's like sugar, once it's used up you seem to run out of energy. They are somewhat better after exercise, because they quickly replenish the muscles. You can look up on google which foods have high or low GI.

Low GI are good for pre-exercise. If you're still trying to lose weight, try this:

Have all your meals be Protein and Healthy Fats (almost no carbs). EXEPT for the meals right before and right after your workout you should eat Protein and Carbs. A combination of Carbs and Fat isn't good for losing fat.