Easiest/best program to correct camera barrel distortion?

Hi, I'm getting a wide-lens camera and know that there'll be quite some barrel distortion on it (in my opinion). What's the best program to counter barrel distortion? Preferably something that doesn't take a lot of computer resources, because the computer that I'll be doing the changes with will be very very old and slow. And possibly free to download from the web? I know that Photoshop has the ability, but is there something out there that can possibly make the correction very easy? Possibly even automatically? Thanks a ton.

I do a lot of architecture photography using a wide-angle lens. My software of choice is Hugin, a free open-source front-end for the Pano Tools filters (written by Helmut Dersch). Although these filters are used by many for panorama creation, they also can be used on a single image to correct for barrel distortion, in addition to horizontal and/or vertical perspective. The results are excellent and far superior to anything built into Photoshop, the Andromeda filters, etc.

I have run Hugin and Pano Tools quite easily on Win95 and Win98 machines, with as little as 233mmx processor, but of course the more processor and RAM, the faster they will go.

A tutorial for fixing barrel and perspective with Hugin is here:
http://hugin.sourceforge.net/tutorials/a...

The Hugin front-end is available here:
http://hugin.sourceforge.net/

And the Pano Tools (the separate filters with a steeper learning curve, but also very useful) can be gotten here:
http://www.all-in-one.ee/~dersch/

There are free programs for picture file editing at www.download.com, but I'm not sure what will run on an old computer.