Pale Moon derivate for Windows XP, made by roytam1, which is based on patches by Feodor2. There is a a discussion about it at the pale moon forums.
Google Chrome for XP
Other browsers available in this list
The following two updates are for whatever browser you use with windows xp. The updates will help with functionality on websites.
You'll need certificate updates. I found several versions of Rootsupd.exe from Microsoft. Contact me and I'll send you a download link if they are no longer available. I also use GeoTrust certificates, and RapiSSL certificates.
Install a more modern unicode font. I found Dejavu font, and within all the fonts in the download, I only installed the Sans and the Serif fonts. In Pale Moon web browser, I then selected the sans, serif, and mono fonts in Tools → Options → Content → Fonts-and-Colors → Advanced.