On wine it can run, but it will have lots of random bugs and crappy performance (I was able to run the steam version of the game easily as it automatically grabs the required dx8 runtimes for you).
If you can manage to run Bootcamp, it should perform better, but 2gb of ram is fairly low for any computer running a modern OS these days.
To find out which OS versions your mac can support, scroll way down to where it says "iMac" on this link and see if you can find your model (
https://support.apple.com/en-us/HT205016 ).
Keep in mind that some older CPUs are 32bit only. On 2GB of ram, if you keep the OS very clean, you could run 32bit win7 without much for issues via Bootcamp and the game would play just fine.
Unless you are extremely strapped for cash, I wouldn't waste my time. I'd focus on picking up a nice cheap laptop, just about any modern non-atom CPU will run the game wonderfully these days (technically atom will too, but for a gaming machine, I'd recommend something with more oomph)
If you need step-by-step hand-holding, go to youtube and search for "Installing Bootcamp", you'll find a plethora of videos, most likely including one specifically for your system version.