Here is the mouse I currently use. I find it comfortable and the batteries last a very long time (haven't replaced them yet and it's been over a year). For only $20 I think it's a very good buy: http://www.amazon.com/Logitech-910-001822-M510-Wireless-Mouse/dp/B003NR57BY/ref=sr_1_1?ie=UTF8&qid=1461601419&sr=8-1&keywords=logitech+mouse
I really like mechanical keyboards; they are a pure joy to type on. I also don't like gimmicks. lights, etc on my keyboards. Really, it's completely up to you, though, for what you enjoy and how much you're willing to spend. I have 2 das Keyboards: one with Cherry Blue switches at work for typing/coding and one with Cherry Brown switches at home for gaming. You can read more about mechanical keyboards here: http://www.keyboardco.com/blog/index.php/2012/12/an-introduction-to-cherry-mx-mechanical-switches/
Here is the model I have:
http://www.amazon.com/Das-Keyboard-Professional-Mechanical-DASK3MKPROSIL/dp/B008PFDUW2/ref=sr_1_2?ie=UTF8&qid=1461601810&sr=8-2&keywords=das+keyboard+brown
And here is the newer model:
http://www.amazon.com/Das-Keyboard-Professional-Soft-Tactile/dp/B00JG01QTY/ref=sr_1_1?ie=UTF8&qid=1461601810&sr=8-1&keywords=das+keyboard+brown
For gaming, beyond the keys, what you want to make sure is it has N-key rollover or anti-ghosting. This is used on USB keyboards to mimic PS/2 keyboards and prevent ghosting (https://en.wikipedia.org/wiki/Rollover_(key)). This is very important for FPS games.
You don't have to spend $100+ to get a very good keyboard, though. If you want to save money, I'd recommend this one:
http://www.amazon.com/Logitech-G105-920-003371-Gaming-Keyboard/dp/B00BBUCCKO/ref=sr_1_2?ie=UTF8&qid=1461602597&sr=8-2&keywords=anti+ghosting+keyboard
If you don't play FPS or just don't care about ghosting, you could save a bunch of money. Probably this one:
http://www.amazon.com/Logitech-920-002478-Keyboard-K120/dp/B003ELVLKU/ref=sr_1_5?ie=UTF8&qid=1461602592&sr=8-5&keywords=keyboard
Honestly, though, this is just my opinion. When it comes to keyboards and mice it's almost 100% what you personally like.