Building my first computer, just have some questions.

First off, motherboards will usually come with some number of sata cables.

Here are my thoughts.

1) The rosewill case is cheap, and will do the job. The Antec 300 is probably cheaper and better.
But, let me suggest the lian li PC Q11R case for a bit more. The quality is outstanding, and the R indicates a red color. The color is stunning; it is not painted, but a red anodized aluminum. I have that color in a V351 case, and I love it. Trust me, pay a bit more for it, and you will not regret it. You will see and touch it every day. $100.
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

2) Since the lian li case is a mini-ITX case which is very small, it takes a smaller motherboard. I have the ECS H55 motherboard in a backup pc, and It has been working well. You will find that mini-itx motherboards will be cheaper, but they have all you will need. $50.
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

3) 4gb of ram is the minimum you should use, but since ram is cheap, and you will be multitasking, I suggest 8gb. Get a 2 x 4gb kit.
There is no need to get faster ram, lower timings, or fancy heat spreaders. Any such benefits are not noticeable. Here is a G.skil basic kit. $80
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

4) The video cards you referenced will work, but they are barely suitable for gaming. I suggest something stronger. Read this article:
http://www.tomshardware.com/reviews/gaming-graphics-car...
For gaming, the graphics card is much more important than the cpu. Get a good one. How about this EVGA GTS450? $130.
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

5) The power supply requirement is mostly determined by the graphics configuration. Antec makes quality units, and you do not need anything very strong for a GTS450. Here is an earthwatts 380 that will do the job. $45.
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

6) The WD caviar black 1tb is a good drive, and it performs a bit better than most. At $90.

7) The Asus burner @ $25 is OK also.

Adding in the i5-750 @ 210, that totals up to about $730. That is slightly over your budget.

I would suggest the following changes:

a) Substitute a i3-550 for the i5-750. It will be $130, and probably be superior for your use. That will save you $80. The clock rate is higher(3.2 vs 2.66). It has two cores, plus hyperthreading. Few games or apps can use more than two cores. The 32nm technology will also run cooler. There is also the capability to use the integrated graphics on the H55 motherboard. I would suggest deferring the purchase of the discrete gaming card, allowing you to better assess your needs. The integrated graphics will run your two monitors just fine, and can play some non-action games like civ2 just fine. I do this on my backup PC with a G6950.

b) The samsung 1tb drive is $25 cheaper, and should still do the job, :
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

These two changes will let you come close to your $600 budget.

c) Lastly, try to find an extra $100 or so in your budget for a SSD for the OS. It will make everything feel so much faster.
The Intel X25-V 40gb drive will hold the OS(about 13gb) and some apps. Watch the market, it is very competitive, and Intel is rumored to launch gen3 drives in a couple of months which will reduce the price per gb. For convenience, though, I would get one now and not look back.
You will be very pleased with a SSD

----------------good luck--------------