2007 iMac Leopard upgrade Snow?

I recently saved an old imac from the the trash. I Leopard installed/250gb/2 gb ram and am enjoying this find.
My question is: Flash player updated won't install> says I need 10.6.8 to continue. Will this slow down the resources of this older intel core 2 cpu?

No, not at all. Quite the opposite in fact -- Snow Leopard is (essentially) a stripped-down, Intel-only version of Leopard (hence the derivative name).

Flash player, on the other hand, WILL tax the resources of your machine (but it does that for everyone!). I'd recommend that you install the latest Flash Player your machine will support, but I would also suggest a plug-in that forces HTML5 where available for video delivery (much MUCH less taxing on the processor) or even blocks Flash selectively (like ClickToFlash for example, which just blocks Flash until you click on the blocked element to OK it).

Thanks Chas.
I'll be upgrading soon.