This is a tutorial on how to delete unwanted trophies from your Trophy Collection on the XMB permanently. Say you have a bunch of games you've downloaded and tried out to find you didn't like the game and are never gonna play it again and you're stuck with a 0% listing of all of its trophies, this will help you remove them completely.
NOTE: This will not work if you have already sync'd the trophies as the next time you sync your trophies they'll be put back onto your PS3 from Sony's servers.
1) First find the trophy folder name for the game's trophies you want to remove.
Example: GAMEZ/BLES00927/PS3_GAME/TROPDIR/NPWR01135_00 (usb) or dev_hdd0/GAMEZ/BLES00927/PS3_GAME/TROPDIR/NPWR01135_00 (internal)
2) Now that you know the trophy folder name you'll need to FTP into your PS3 and delete the installed trophy folder for that game or simply use multiMAN or Comgenie's Awesome File Manger.
3) Now when you look at your Trophy Collection on the XMB you'll notice that the games trophy image is missing, displaying a default gray image.
4) Load up that game again in your manager of choice, Gaia, Multiman etc.
5) Start it as you normally would from the XMB and when it starts the trophy installation it will error out and dump you back to the XMB.
6) Check your Trophy Collection and you'll now see that the games trophy listing is now permanently deleted.
7) Repeat for any other game trophies you want to remove from your Trophy Collection.
Have any questions, just ask.