If you are able to see those files that you want to delete with Ovi Suite, then you can simply delete them with Ovi Suite.
You are also able to see the phone on Windows explorer to delete files
thanks for your reply but still i have trouble.
I cant delete thems which i dont like it.
And i cant delete songs which i dont like. I try to found Ovi Suite in my Nokia C5-03 cellphone.
You can find Suite from www.ovi.com/ovisuite.
Unfortunately I don't know how to delete themes, but music you can find also with Windows explorer (What OS you actually has on your computer: XP,Vista or 7)