An example is the Raleigh C500 you mention. It's $550, and has a suspended front fork to smooth out potholes and help with those curbs. It even has a suspended seatpost, and a fat, comfy saddle. The frame is aluminum; the 27-speed drivetrain is Shimano. In fact, just about every bike in this category and price range will sound a lot like that, spec-wise. Cannondale's Adventure 400S ($525; www.cannondale.com), for instance, is a near twin to the C500. The Cypress LX is a nice bike, but pretty hefty at 33 pounds, so maybe not the best for any sort of sporty riding.
My advice: Go to a bike store and try several bikes in your price range. Compare them on weight, fit, and overall comfort. Have a salesclerk explain to you in plain English how they differ from one another technically. You might also find a true "mountain bike" that works for you. If so, have the shop swap out the knobby tires for smooth or low-tread ones, and maybe add a suspended seatpost.
Remind them, too, that the 2004 models are on the way and they need to clear merchandise. Then try: "So how about $50 off?"