In Starcraft 3 races, Terran, Zerg, and Protoss struggle for supremacy in the known universe. The campaign is relatively imaginative, the missions are mostly well manageable. In the MP, the AI is just really fast, especially if you have installed the patch. Broodwar is the expansion of the game. It is advisable to play Starcraft first, then the expansion, because the missions in Broodwar are quite tough from the beginning. Depending on whether you installed the expansion or not, you only need one of the two patches.
SC is still available at Blizzard. You can also exchange an already owned CD key for a web installer key by linking your key to a Blizzard account and then use their web installer. This is not bad in combination with the patch, because you don't need a CD anymore.
The installation is quite simple. First SC, then install the addon Broodwar. Patches are applied accordingly. But it's recommended to install Broodwar completely, because of new units and more missions (also helps a lot in terms of storyline, especially if you want to play Starcraft 2). The patches only work if you have a normal installation, nothing copied. The installation path will is stored (probably in the registry). The patch installer needs that, otherwise it won't start. Alternatively, you can simply use a pre-installed version. You should have already installed the last patch (1.16.1). There won't be a newer one from Blizzard. There is a German and an English version. The latter don't needs a CD anymore. The installed version is supposed to be the same after applying the patch (but I haven't tested it yet). Mini images were once meant to outwit exactly this CD query. If someone can confirm that Patch 1.16.1 doesn't query the CD anymore, you can save that.
SC was created at a time when nobody thought about Windows 7 and its peculiarities. There is the palette bug, which can happen under Win 7 with the CD version, so that a lot of false colors are displayed. The palette is ruined and it helps to quit the Explorer during the game. See also Explorer Hack. It happens occasionally that SC takes a very long time to ask until it actually starts. Don't let this worry you. If in doubt, open the task manager (
ESC) and check if the
starcraft.exe is already running. If so, just wait, that will come.
The game is playable in the LAN. But it turned out that you can't get around the patch, as the game works very unreliably with IPX. UDP is the protocol of choice here. Therefore the patch is also necessary, as UDP is only available with patch. The other possibility is via the Blizzard servers, but you need a valid CD-Key and under Win 7 x64 it will mess up the graphics a bit, so you can hardly work with the interface anymore. These problems don't exist with the game via the Battle.net client.