What's the differences in the iPod 5 and the iPhone 5?

I'm deciding whether to get an iPhone 5, or an iPod 5. But first I need to know what are the differences between them, besides that one has built in calling an texting an the other doesn't. Also what are the pros and cons of each?

IPhone 5 lock button not working? - 1

My iPhone 5 lock button won't work anymore and I've heard that a lot of people have been having this problem. How can I fix it? I know about the assistive touch but I don't really like using that, but where can I actually fix my lock button? I called the apple store and the operator wouldn't let me speak to a representative unless I have a warranty plan. So is there a store or another place I can fix it at? Or is there a way I can fix it myself at home?

Why isn't my iMessage working?

I have an iphone 4 and today all of a sudden my phone started sending text messages instead of iMessages but in my settings it says that my iMessage is turned on so I don't know what to do!

Added (1). No the people I'm texting have iphones i'm not that dumb haha but it's not working with everyone

If I take my iPhone to apple will they replace it?

I have an iPhone 5 and it's still under the one year warranty. Very often my phones keyboard will stop working or an app freezes and won't unfreeze unless I turn my phone on/off. Will they replace it if I tell them this?

Can you flash an iPhone to Straight Talk?

Someone I know is about to end their contract with AT&T and she has an iPhone 3. She said she is willing to give it to me and I was wondering if I could flash it to Straight Talk? If so how? Because I looked on Straight Talk's website and it says that you have to classify it as a GSM or a CDMA. I have no idea the difference or how to look. Any information is helpful.

How to speed up my Iphone 3gs 8gb?

I have an Iphone 3gs that is 8gb, I used up about 5 of the 8gb, and it is extremely slow! I was wondering how to speed it up! It didn't start going slow until after the last Apple Update in Januarary 2013!
Also is their any Prepaid gsm plans that is cheap with a good amount of data, and also unlimited texting? And by cheap I mean not over $50.00 per month.