Iphone 4S screen and aux replacement costs
For price quotes it's probably best to contact an Apple Store in your country directly, because prices will vary around the globe (so a quote for UK won't help you much if you live in India for example). The people in the Stores are there to help you (and are usually quite good at that) and they will also be able explain to you the difference between having your phone repaired or getting a new one.

Alternatively there might be other repair shops in your area which offer screen replacements and other services. Their prices may be lower, OTOH if more than just the screen is broken (as it seems to be in your case) they might not be able to fix your phone.