any other boy or boys

[Snappy]

In my understanding, only (a) is grammatically correct.
(a) He is taller than any other boy in his class.
(b) He is taller than any other boys in his class.

Then which one of the following sentences is better?
1)The two boys are taller than any other boys.
2)The two boys are taller than any other boy.

I have another question.

What about the following case?

These shoes are more expensive than any other shoes/shoe in this store.

[2006]

In my understanding, only (a) is grammatically correct.
(a) He is taller than any other boy in his class.
(b) He is taller than all the other boys in his class.

Then which one of the following sentences is better?
1)The two boys are taller than all the other boys.
2)The two boys are taller than any other boy.

2006

[2006]

I have another question.

What about the following case?

These shoes are more expensive than any other (pair of) shoes in this store.

Since shoes usually come in pairs, we can say 'These shoes...........any other shoes......'.

1...When you have a follow-up question, don't add it to your original post. It could go unnoticed there.
2...When someone answers a question for you and you have another question, it wouldn't hurt you to say 'thank you'. Nobody here is your servant.

[Snappy]

1...When you have a follow-up question, don't add it to your original post. It could go unnoticed there.
2...When someone answers a question for you and you have another question, it wouldn't hurt you to say 'thank you'. Nobody here is your servant.

Thank you for your answer and advice. I will keep your advice in mind.