Due to Adobe stopping support of CS2 it left many past purchases screwed if they moved computers, so Adobe were forced to release the complete CS2 Suite. Although you are supposed to be an owner of the software already, nothing stops you from downloading it and installing it now, and Adobe even supply the official serial numbers.
Some of the CS2 suite may not work correctly on W7/W8 but you can change the compatibilty mode on them to switch to XP/Vista mode. (Right click on the Icon>Properties>Compatabilty).
You can download the CS2 suite as indivual programs or the complete list of software. The latter is huge, and is a BIN file that needs to be burnt directly to disk.
I advice downloading them one at a time, even if you think you may not require the software, you never know in the future.
Remember, you are actually only allowed to download the software if you have previously purchased it.
http://www.adobe.com/downloads/cs2_downloads/index.html