*I would like to know if its possible to delete just a music or another file from ipod classic without using itunes.*
No you can't delete directly from an iPod you have to connect to your computer and iTunes.
*If I try using itunes I just can syncronize all the library, if I try just a file the rest is deleted too*
How you delete content from your iPod depends how you have it set to update:
If you are updating automatically (syncing) all songs and playlists then delete the files from the iTunes library. In the iTunes Library highlight the file and press the delete key on your keyboard. If you're updating the iPod from a selected playlist delete the song from the playlist and it will remain in the library. Next time you connect they will deleted automatically from your iPod.
You can also update your iPod manually and delete manually. If you are updating manually, connect your iPod and when it shows in the iTunes 7 source list click on the chevron (the little triangle) to the left of the iPod icon This will display the various icons for the iPod itself, Music, Movies, TV Shows and Playlists. Click on Music and you'll see the usual song list. Find the files on your iPod that you want to remove, highlight them and delete directly as above by pressing the delete key on your keyboard.
To select multiple items such as all the songs in an album, click on the first track in the list hold down the shift key and click on the last track to highlight the selection. Then press the delete key.
To summarise, you start by highlighting the song/video/selection in either the iTunes library or on the iPod song list as displayed in iTunes then press the delete key on your keyboard:
Deleting songs or playlists from your iPod
