The NPi 2 does get very hot, with use, but not usually at boot up, I fitted a small heat sink on mine just out of paranoia, rather than any issues I might have. Its really not a bad thing to do on any board which has hot chips, they will last that little bit longer for a tiny investment.
The sticking at the credit screen is basically the problem I was having with one particular bad SD card I had.
I have had a few issues with units when using bad/cheap/fake TF cards, even though you are pretty sure your card is good, there are a lot of fakes around, try another, one that you know was bought at full price. and make sure you test it before you burn it.
2A's is plenty of power for it, is it a wart that has its own micro usb cable out? If its a usb plug in, I have found those to be very unreliable, also what do you have plugged into the USB, I don't think it has a very high tolerance for multiple units on a hub which can drain the power to the board and cause a freeze/reset.
But really, it could be anything, the chip does get hot, but can operate at quite high temps,I don't know the actual max temp, but as a rule, if you can't touch it, then its certainly overheating, and if that happens at boot, its almost certainly faulty, as it should take a good minute or 2 for it to get uncomfortable to the touch.
If in doubt, send it back.