Types of Dietary Fat

QUESTION 1: Does all dietary fat fall into one of the following four types: trans, saturated, monounsaturated, polyunsaturated? Why don't they always add up to total fat in MFP?

Is it because unsaturated fats are usually not listed on labels, so MFP plugs in Zeros for them? If that's the case, shouldn't I just ignore the daily/weekly total for poly and mono in MFP and assume that my Total Unsaturated Fat is equal to Total Fat minus Saturated Fat?

QUESTION 2: If my total fat intake is actually too low, then I need to increase it, right? See below.

Background:
I am on a new diet. Scratch that. I'm not on any fad diet, I am counting my calories and learning to eat healthy with MFP. As such, I am trying to be conscious of fat intake. Keep it between 20%-30% of total calories, eliminate trans fat, reduce saturated fat, and increase the two unsaturated fats. Specifically, from what I understand, I am trying to get at least 50% of my fat from unsaturated fats.

My diet is now often so low in fat (sometimes under 20%), that I feel the need to supplement with 'good fat' in order to ensure uptake of vitamins, etc. Typical day:
Breakfast: oatmeal with veggie smoothie (low sodium V8, spinach, carrots, jalapeño, lime juice)
Snack: Fruit (plumb, orange, apple)
Lunch: 2 Sandwhiches (whole wheat rounds, low sodium turkey slices, pickle, mustard)
Snack: Protein bar
Dinner: Chicken breast, brown rice, mushrooms, steamed broccoli, green beans (some times pinto beans or pasta)
Desert: Green smoothie (Greek yogurt, nonfat lactose free milk, frozen berries, banana, spinach, carrots, stevia, cocoa

See, almost no fat, right? So I take a fish oil pill and eat a few almonds. Should I be adding some oil to those smoothies?

By the way, I previously ate fast food, junk food, and few veggies. I'm not big on veggies, but I am trying to get as much fruit and veggies as possible, no trans fat, complex carbs. I tend to eat a lot of protein, too much. I know I need to eat more fish.

Thanks for your input!