Is Rage (PS2) Two-Player?

No. Rage (the 2011 id Software FPS) was never released on PlayStation 2.

You may be confusing it with:

• Rage (2011): Released on PS3, Xbox 360, PC — single-player only (no multiplayer at launch; co-op added later via DLC on PC/consoles, but not split-screen).
• PS2-era shooters with "Rage" in title: None exist.
• Road Rage (2003): PS2/Xbox/GC — Crazy Taxi-style game, single-player only.
• Street Racer / Twisted Metal / Burnout: PS2 vehicular combat/racing games with split-screen multiplayer.

If You Want Split-Screen FPS on PS2

Try these classics:

• TimeSplitters 2 / Future Perfect — 4-player split-screen, bots, map maker.
• Killzone — 2-player co-op campaign + versus.
• Red Faction II — 4-player split-screen.
• 007: Nightfire / Everything or Nothing — 4-player split-screen.
• Star Wars: Battlefront II (2005) — 2-player split-screen (PS2 version).

Verdict: Rage is not on PS2. For split-screen shooters on PS2, TimeSplitters 2 is widely considered the best.