How can I get Netflix to stream movies instantly on my Mac?

[any ANONYMOUS forum user]

I have a Mac that meets the system requirements. I have enough memory. I have the compatible browser software...and yet, if I hit "Play" on a streaming Netflix movie, I get a box saying that they don't support my operating system (Mac 10.5.8), and that I need Mac v. 10.4.8 or later -- which, obviously, I have. Naturally, there's no way to reach customer support .

Does anyone have a solution? My local Blockbuster has closed and itunes has very limited selections, as does On Demand. How can a person watch a movie without waiting for a Netflix delivery by mail?