Go widescreen.
First, they're generally cheaper, so you'll get more bang for your buck.
There are two possible complaints:
1> Old games/video/etc are stretched and funny looking.
This can be addressed in the video card settings for most video cards. If you're using a DVI connection, NVIDIA cards will allow you to center the image with black bars on either side to prevent the stretching.
2> Working on a single document is too wide.
There are two solutions to this... don't do it any more being the harder one to get in the habit of. Stop running maximzed windows and let them scatter about and be next to each other.
The other solution, presuming you're using Windows, is to grab the task bar and drag it over to the right or left edges of the screen and make it kind of wide. Your desktop is squared back to the older shape, and you gain a little vertical space back from the task bar. I also usually have too many windows open to fit in a horizontal task bar, and can get may more in the vertical.
Widescreen has been good, and today I wouldn't hesitate to go any other way.