First time building a gaming pc.HELP.

What is your budget and where will you be buying your parts from?

From what I see in your initial list, your H97 motherboard should be changed to a Z97 so that you can overclock your "k" cpu. For the PSU, if you select the 960, you'll need only 430W. For the 970, you'll need 500W. It is best to select a high-quality PSU. If you are limited with the Corsair brand, avoid the CX series and the VM series. You might get away with the CS and RM series but I wouldn't highly recommend those too. If you are limited with the Thermaltake brand, choose only the ToughPower Gold/DPS Series. Note that there are other PSU's that are more reliable. For your RAM, I suggest going with a 2x8GB instead of the 4x2GB.

I'll suggest a build for you considering your budget (will post it later).

For the the 16GB-RAM, you want to choose the 2 sticks over the 4 sticks. The 2 sticks would have less stress in the memory controller and you have the option to upgrade (in the far future) for another pair of 8GB to max out the memory capacity of your mobo (but I doubt you will ever need more than 16GB for many years to come).

The RM, RMi, and HXi of the Corsair PSU's all have their different specifications. The primary goal is to first select the required wattage that your rig needs (which are dependent on the GPU you will select). The next goal is to decide on the efficiency rating (80+ Bronze, Gold or Platinum). The Gold and Platinum works best if your rig will be running 24/7 since the efficient operation of the PSU saves yearly electricity costs. If you turn on your PC just once in a while, an 80+ Bronze would be alright. The last goal is, of course, the cost. Select the price that fits your budget.

The Z97 has different models depending on the manufacturer. Check out the Asus, Asrock, Gigabyte, and Msi motherboards and compare. There are countless of models to choose from. Basically, motherboard models differ in the number of RAM slots and memory capacities, number of PCI/PCIe slots, capabilities for multi-GPU (SLI or CrossFire supports), number of USB and SATA ports. Some models may have additional features such as on-board Wi-Fi, m.2 ports and USB 3.1 support. Then, of course, there are the different sizes which are ATX, micro-ATM/mATX and mini-ATX/ITX.

All the models you are asking (Z97-A, Z97-K, Z97-PRO GAMER, and Z97-PRO) all pertain to Asus Z97 Motherboards. Note that other brands have different names of models.

Let's first look at the similarities of these four Asus Z97 motherboards:
They all support Intel CPU's with Socket 1150
They all have the Intel Z97 Chipset
They all have 4x Memory Slots that are Dual Channel and supports DDR3-1333MHz up to DDR3-3200MHz (O.C.)
They all support Integrated Graphics (on-board GPU) with 1x DVI-D, 1x D-Sub (VGA), and 1x HDMI rear ports
They all have 1x LAN (RJ45) rear port
They all have 4x USB 3.0 and 2x USB 2.0 rear ports
They all have 1x PCIe 2.0 x16 Expansion Slots (usually used for a 2nd video card for multi-GPU)
They all have 1x M.2 Socket 3 Storage Support (usually for M.2 Solid State Drives)
They all have a total of 6x USB 3.0/2.0 Ports
They all support Windows 8.1, Windows 8, and Windows 7 Operating Systems
They all are the same sizes (ATX Format)

Now let's take a look at their main differences:
Z97-A vs Z97-K vs Z97-PRO GAMER vs Z97-PRO

Colors/Theme: Black/Gold vs Black/Gold vs Black/Red vs Black/Gold

PCIe 3.0/2.0 x16 Expansion Slot: 2 vs 1 vs 2 vs 2 (This is where you install your video card)
PCIe 2.0 x1 Expansion Slot: 2 vs 2 vs 2 vs 4 (This is where you can install wi-fi adapters, sound cards, etc.)
PCI Expansion Slot: 2 vs 2 vs 2 vs 0 (Older type of slot where you can install wi-fi adapters, sound cards, etc.)
Multi-GPU Support (NVIDIA): Quad-SLI vs None vs Quad-SLI vs Quad-SLI (# of additional video cards by Nvidia)
Multi-GPU Support (AMD): Quad-CrossFire vs Quad-CrossFire vs Quad-CrossFire vs 3-Way-CrossFire (by AMD)

LAN: Intel I218V vs Realtek 8111GR vs Intel I218V vs Intel I218V (For Internet/Router Wired connection)
Audio Codec: Realtek ALC892 vs Realtek ALC887 vs SupremeFX vs Realtek ALC1150 (On-Board Sound Card)
PS/2 (Keyboard/Mouse) Rear I/O Port: 1 (Combo) vs 2 (1x Keyboard + 1x Mouse) vs 1 (Combo) vs 1 (Combo)
Display Port (DP) Rear I/O Port: 1 vs 0 vs 0 vs 1
Optical S/PDIF Out Rear I/O Port: 1 vs 0 vs 1 vs 1
Audio Jack Rear I/O Port: 5 vs 3 vs 6 vs 6

Internal USB 3.0 Connection (USB 3.0 Front Header): 1 (2) vs 1 (2) vs 1 (2) vs 2 (4)
Internal USB 2.0 Connection (USB 2.0 Front Header): 3 (6) vs 3 (6) vs 3 (6) vs 2 (4)
SATA 6 Gb/s Ports: 4 vs 6 vs 4 vs 4 (# of storage devices/HDD/SSD/ODD with SATA connection you can use)
SATA Express Connection (Additional SATA 6 Gb/s Ports): 1 (2) vs None vs 1 (2) vs 1 (2)
CPU OPT Fan Connection: 1 vs 0 vs 1 vs 1 (# of additional fan/cpu fan you can plug in)
Chassis Fan Connection: 4 vs 2 vs 3 vs 4 (# of case fans you can plug in)

So, with these differences, you have to decide in which do you think you will only need (such as # of HDD, # of GPU's, USB Devices you will connect, Color Theme that you prefer, etc.).

Now, the only differences of the H97-PRO GAMER between the Z97-PRO GAMER (other than overclocking abilities) are the following:

• 
  Supports Memory Speed of DDR3-1333MHz and DDR3-1600MHz only (due to lack of overclocking of RAM)
  
  Does not support SLI (Nvidia multi-GPU); only Quad-CrossFire (AMD)
  
  Only 1x PCIe 3.0/2.0 x16 expansion slot
  
  Has 3x PCI expansion slots
  
  No Optical S/PDIF out at rear port

Here's my suggestion of all your parts list:

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4690K 3.5GHz Quad-Core Processor ($229.99 @ SuperBiiz)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler ($24.99 @ Newegg)
Motherboard: ASRock Fatal1ty Z97 Killer ATX LGA1150 Motherboard ($92.98 @ Newegg)
Memory: G.Skill Ripjaws X Series 16GB (2 x 8GB) DDR3-2133 Memory ($88.99 @ NCIX US)
Storage: Samsung 850 EVO-Series 120GB 2.5" Solid State Drive ($66.89 @ OutletPC)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($50.89 @ OutletPC)
Video Card: EVGA GeForce GTX 970 4GB FTW ACX 2.0 Video Card ($319.00 @ NCIX US)
Case: Corsair SPEC-02 ATX Mid Tower Case ($49.99 @ NCIX US)
Power Supply: Antec High Current Gamer 620W 80+ Bronze Certified Semi-Modular ATX Power Supply ($61.98 @ Newegg)
Optical Drive: Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer ($15.98 @ Newegg)
Total: $1001.68
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-09-11 13:00 EDT-0400

It's not the brand that should be decided on, it should be the model or product of that brand.

For example, MSI produces one of the best motherboards and GPU's in the market (very high quality). However, they also produce PSU's (very low quality).

Another example, EVGA SuperNova NEX Bronze and Gold Series are Tier-4 (low quality) PSU. But, EVGA SuperNova GS and PS Series are Tier-1 (high quality).

So, take an in-depth look at the product/model these brands are offering... not the brand itself.

You're welcome! Glad to be of help.

That affordable cooler is good for light overclocking (price/performance -wise it's a steal). However, if you plan to really stress your CPU to it's max. I strongly advise to go with liquid cooling, just like that Corsair H100i or GTX you initially-selected (IF you can afford that within your given budget, because it's a lot more expensive than the Cooler Master air cooler).