interest VS. interests / that I don't agree VS. I don't agree with

Could you help me understand few of the concepts that i'm confused with?
I would appreicate it if you explain them as easy as you can make it.
I appreciate your time and response in answering my questions.
thank you.

These are conversations between two people:

1. A: Tina, do you prefer watching movies or playing sports?
B: Well, watching movies _____ me more.

(a) interest
(b) interests
(c) is interested in
(d) are interested

I know (c) and (d) are incorrect b/c .... I don't know... they just sound wrong... is there grammarical reason for why they are wrong? plus of these two choices (a) and (b), why is (b) correct answer? is it because having an extra -s makes it singular form? or is there another reason?

2. A: People living in large cities are usually stressed.
B: That's a generalization _______.

(a) I not agree
(b) that I don't agree
(c) I don't agree with
(d) I don't agree with that

(a) is incorrect because not needs BE type of verb [am, is, are...] in order to make it negative and in order to make sense... right? and (d) doesn't work because of that... I don't know it just sound wrong... is there grammarical reason for why it is wrong? lastly, of (b) and (c), why is (c) correct answer and not (b)?

[QUOTE=dong6241;862291]1. A: Tina, do you prefer watching movies or playing sports?
B: Well, watching movies _____ me more.

(a) interest
(b) interests
(c) is interested in
(d) are interested

The gerund 'watching' functions as a singular noun, and we therefore need the 3rd person singular verb-ending -(e)s.

c and d are wrong because 'watching movies' is not interested in anything; it may be interesting for you.[QUOTE]