I have a 17" early-'07 iMac 1GB/160GB. I don't do a whole lot with it besides email, word processing, and web stuff. It's also serving as our "home theater" - and that's the rub. The display is just too small! So my question is, if I'm otherwise happy with the 17", does it make sense to just get a ~24" second monitor ($200 or so), upgrade the RAM by throwing a $50 2GB unit in there, and upgrade the OS to Snow Leopard? It seems like dual monitors would be a bit unwieldy, but a whole lot cheaper than option 2, which is getting the bottom-of-the-line 27" iMac (or there's always the 24"). If I get a new machine I could get a ~$300 trade-in credit on the 17", so the cost difference is less than it seems. Pros/cons? How long will the 17" continue to be useful for if I upgrade as outlined above? Help me vanquish the paradox of choice! TIA.