I'm not sure what you mean by "overly widescreen" - are you looking at these screens in person or on the web? How can you tell they're overly wide?
I'd be far more concerned with display quality than display sizing. The Dell screens I've used in the past have always been terrible at getting the color quality that a macbook pro screen has.
I'm currently using a Samsung 2333HD next to my MBP and it's a serious competitor to the apple display quality, in my opinion. To be fair, it's just under your specs at 23" but it's more than enough extra screen real estate for me and you'll surely be impressed if you're upgrading from a 19".
The newest apple display is 19.35"x25.7"x8.15" (and that's for a 27" screen) whereas the 2333HD is 16.5"x21.8"x8.5" (for 23") so very close to the same depth and 3"/4" less height/width for 4" less screen size. It's the same 16:9 aspect ratio, so you probably won't be disappointed by the width and, again, you definitely won't miss out on quality. Seems like it runs around $200 these days, I got mine for $150 on sale so you could probably search around a bit for a better price.