Firstly I'm gonna upgrades/compromises that will give you a better system
CPU- you've chosen a great CPU, if you have any spare money, look at the 4770k it's by far the best lga1155 CPU
GPU - that's is a brilliant choice, I have the same gpu just the 4gb version! If you have the money look at the 4gb version just to future proof but don't worry that gpu will serve you well and you'll be happy with it
Motherboard - there's one simple rule here the difference in performance between an atx mini and say a asrock extreme11 (one of the best boards) is barely noticeable so don't worry about if the board will be good enough, just buy one that has the features you'll use and no more.
Ram - another rule here, again diff between 1333mhz and 2400mhz is around 1-2 fps in gaming so really there's no point in buying high frequency ram just a waste of money..
Ssd - great choice! I have that same ssd so great!
PSU - will be great, if you want to make sure you have enough wattage for future upgrades, try a site like thermaltake psu calculator
Ok I hope that helps! Just remember there a literally tens of thousands of reviews and comparisons so always use them! Good Luck
Oh and as for the warranty question I'm not sure what you mean, but the warranty from the store is usually 30 AFTER you receive the goods/AFTER the goods have been shipped. As for the product they are all independent depending on the company usually from 1 year - 5 years, that's of service/repair warranty. Hope that answers your question