(Sorry about the nearly two year late response)
What you want to do is to find a download for it (perhaps a torrent) *Spock

*. Go to google, type in 'Battlezone 2 download' and click search. Find a suitable download.
Click download and save the file somewhere where you can go and get it later. The chances are that you will get a message saying that (depending on your OS) your computer can't open the file and that it suggests you should manually pick a program to open it with. What you open a file like this with a program called a 'BitTorrent Client'. I use BitTorrent or uTorrent, but there are loads of other programs that you can use like Azureus or Vuze.
Search for one of them BitTorrent Clients and find one you like best and download it.
Once you have downloaded and installed utorrent, find the battlezone 2 torrent file that you saved and open it with uTorrent. To do it, you click once on the file so that you highlight it, then where it says 'open' or 'open with', click on the drop down arrow and select 'browse'. Find the uTorrent program, then click OK.
This will bring up the program with the battlezone 2 torrent file. Click something like start download. Most torrents take an exceptionally long time to download than conventional downloading, because with torrents you are sharing component files and bits and pieces with other downloaders or 'peers'. Some people who have already finished downloading the file then begin to upload it back onto the uTorrent network, helping others to speed up their downloads. This is known as 'Seeding'.
Don't be alarmed if the estimated download time says something like 3 days, it will eventually speed up and that time will become a lot shorter.
I hope this helps. (And I also hope that the time it took typing this up was worth it

)
*****I HAD TO EDIT THIS POST BECAUSE GIVING LINKS TO TORRENT SITES IS AGAINST THE FORUM POLICY***** Also, I couldn't edit my post because I think there's a time limit for editing a post and I obviously passed it.
but yeah, just use *cough* utorrent *cough*. 