My home-office is where I do most of my old-school gaming. There I have a late 90's JVC tube TV (which I bought new and am surprised I still have after all these years) and Philips boom-box for audio. All of my consoles are composite, run through 2 daisy-chained 4-button a/v selectors: US Duo, NES, Genesis, Dreamcast. Also I have a DVD recorder hooked up so I can record my gameplay when I feel like it.
The living room home theater has a 47" LCD, Onkyo receiver, Bic F-12 sub, Polk speakers all around, and: Xbox 360 (w/ HD-DVD player), PS2, SNES, Gamecube (w/ GBA adapter) and Turbografx-16 w/ CD attachment.
Those are the systems I have most commonly set up, though every once in awhile I'll dig out some of my lesser-played consoles.