Stop hunting for broken links and shady forums. Open Steam, pay the $10, and experience the Gravemind, the Scarab, and the Legendary Jackal Snipers the way they were meant to be played.
If you want a that works instantly, supports 4K resolution, 144hz refresh rates, and has a thriving online multiplayer community, the only official answer is Halo: The Master Chief Collection (MCC) on Steam. Halo 2 Pc Game Download LINK