Am I correct in understanding that:
-If I buy a set of OEM disks I can install them on one (1) computer, I could not uninstall that copy and reinstall it on another computer.
-If I buy the $200 (newegg $180) retail version I could transfer the license to another computer.
Yes, you are completely correct. Since you pay double upfront for retail copy, they better damned well let you transfer it, right?
So, I guess OEM is the way to go if I am building a computer.
OEM is pretty much the way we all go when building computers.Technically, an OEM copy of Windows must be purchased in association with permanent hardware, a board, a CPU, memory. If you were to walk into Microcenter, you would be required to have made these hardware purchases within the past 30 days, or you wouldn't be allowed to purchase OEM Windows. I'm not exactly sure what Newegg's policy is, since I'm constantly buying hardware from them.
The best way to keep everybody happy, is to simply order the OEM copy of Windows with the motherboard, and done!
Also keep in mind that with OEM Windows, you must choose 32 or 64 bit. Retail copies have both versions. I suggest 64 bit with Windows 7. If you're building a machine from current parts, you won't have any trouble finding drivers for it.
OEM, (and retail), Windows, allow the replacement of hardware over time, in this sense they are very similar. Points are assigned to different devices, and allowances are made for attrition and upgrading.
You can even change the motherboard with an OEM copy of Windows. (This applies to a you-bought OEM copy, not an OEM copy that comes with a pre-built computer).
However, in the instance of a motherboard replacement, Windows would require reactivation, and I would absolutely avoid changing any other parts at the same time