Check out Fishell R3 which is a Shell OS Type homebrew for you PSP. Updates in R3 include bug fixes from earlier versions plus support for more languages. Unfortunately at this time English isn't one of the supported languages however the dev plans adding that in the next release.
Here is a partila statement from th dev. Full changes can be viewed at the source.
" 75% of the code is now public for users (the other 25% is encrypted for security)
* Added file selector included in some internal functions of the shell (use Explorer-like file).
* New feature MSS (Memory Stick Sender) allows you to send files between PSPs via the Memory Sticks (for now only files).
* Added support multi Idoma pora added now to the French (led 90% of the shell for now)
* Added new installer / updater Fishell Fishell PC (requires java)
* Compatibility plugin categorize a game.
* totally rebuilt the mp3 player (inspired limewire pc) (BETA Stage).
* New System Installation and Upgrade (no longer require 2 packages, you can install or upgrade to one)
* Added auto garbage collection system (released every so often you may get the RAM crashes on psps 1000).
* Possibility to display the complete Fishbar (optional).
* Enabled the option to log output from the menu.
* Added ability to install plugins from the file browser (double click the file. Prx).
* Added option to reset the system recovery menu (reset user accounts and system settings to default in case of having a constant error)."