I would really appreciate as much advice as possible

[Argo]

Ive gotten ahold of a few random parts and I want to spend as little money as possible to assemble a PC out of them. A possible problem(please point it out if you see it) is that some of these parts aren't compatible with each other. The parts that I have are:

Video card: Gigabyte GeForce 8800GT 256MB/256bit
PSU:OCZ500SXS 500w
RAM:2x 1GB sticks of OCZ PC2 6400, 4-4-4 @2.1v
Heatsink/Fan: Coolermaster Vortex 752(heavy and worries me)
Motherboards: Gigabyte GA-M61PME-S2 Specsfound here
and also this motherboard:Asus M2N-VM DVI
CPU: AMD Athlon 64 X2 4200+ Brisbane 2.2GHz 2 x 512KB L2 Cache Socket AM2 65W

The problem here is the motherboards are both Micro ATX and I need to decide on a computer case. The question I have is, should I be looking for a Mini tower or is it possible, if not a better idea, to get a regular sized tower and would the motherboards fit? Before I ask anymore questions, here are the three final parts I need in order to have a running computer, which I would appreciate suggestions for. Low cost is a very high priority for me:

1)Optical drive. I'm just looking for your standard DVD player/burner.
2)HDD. The cheaper the better, I don't need disk space and I'm sure the smallest disk space capacity with SATA connectors available on the market will do for me.
3)Case.

That in mind, what is your advice for me to put these parts to use? I failed to address what the computer will be used for: Browsing the net and playing media comes in as first priority, playing older PC games comes in second. My goal is to avoid high costs and avoid incompatibility hassles and as quickly and painlessly assemble the parts for the purposes I mentioned. Thanks for any help.

[flanzig1]

1: An Asus or Lite-on DVD burner(retail) from Newegg are under $30.
2: A 250 gig is probably the smallest for the latest version of HDs. 500gig maybe the most common size.
3: Get a standard mid-tower case, will have room for expansion and a uATX mobo will work that size case.

[Argo]

So you suggest getting a standard Mid-Tower, and I will not have problems with assembling either of my two micro-ATX motherboards in it? If so, which of the two boards should I use if this is what's best?

[Alaron]

Either motherboard will work, they are similar. I'd go with an Asus brand board myself.

Standard ATX towers have mounting holes for both ATX and mATX, no worries.

[not important]

I would also suggest the Mid-Tower ATX case. It will be easier to work in and gives you room for a larger MOBO if you ever have the need..
For an optical drive........LG or Lite-On.