Which lightweight linux distribution can you recommend me to install in an old compaq presario to use just for web browsing and other simple tasks?

I have an old compaq presario C500 that i’d like to use in my home to have easy access to the internet and maybe other activities like watching images from a usb drive and so.

I was thinking about installing ubuntu (basically the only distro i’ve used besides debian), but I think it may be too “heavy” for the computer, since it has just a celeron M processor (at 1.73Ghz) and 512Mb of RAM memory.

I would like to install a really lightweight distro, that runs smoothly and start quickly, but I don’t know any other besides debian-based distros, I’ve googled about it but I would appreciate your opinion and read about your experiences, thank you ;-)