There are devices that will upscale the image for you, I can't think of what they're called, but you'll find lots of useful information by browsing the forums at
www.avsforums.com
And some tv's already have good scalers in them, they're not all created equal when it comes to displaying 480i and under content. Some can do a decent job out of the box on everything, while others will do a poor job of upscaling anything and will always look bad with anything beyond the native res of the tv.
As for what you want to do, I don't get it. I haven't played on a LCD yet that doesn't blur, even if its ever so slightly, on slow moving games like Super Mario Brothers (Let alone something that is moving around quickly and switching directions with something like Ecco the Dolphin), though blurring isn't very noticeable with 3d stuff. And you'll introduce the likelyhood of input lag with the scalers where what your seeing is a split second behind what's actually happening in the game, throwing off your timing.
Your just going to hurt your experience for everything before the Sega Dreamcast (Which will look good on a hdtv if it has a VGA input and you buy a Dreamcast VGA cable, with most of the good Dreamcast games supporting progressive scan). Most Playstation 2 titles will look bad since most couldn't even do 480p(Some are also known not to play on some hdtv models through component, such as Ico, because the tv isn't prepared to accept the low, below 480i resolution through the component input).
And you'll have black bars unless you really could care less how your games look and stretch it to fill a 16:9 television, something that some people don't mind and prefer over having the black bars, but something I don't understand since you will be distorting the entire image.
And it will never look as good as playing on a 480i CRT television. Unless its a Xbox, GameCube (If it has the component port and you have the rare component cable), Sega Dreamcast, or a current generation console, you'll be negatively affecting your experience in your quest to rid yourself of a superior type of television. Its too bad CRT technology is so heavy and bulky, because it gives the superior image easily. But it loses a lot of practicality when it comes to larger screen sizes and widescreen support, even though hd CRT's are superior to other HD sets when it comes to visuals.