ohh and to edit menu background. just find a nice theme. that changes it.

u can find themes at

Mobile9 - Free ringtones, free themes, free wallpapers, free videos, free software, free games for mobile phone
Zedge: Free ringtones, free wallpaper, free themes, free downloads to Nokia and other mobile phones.
Free Ringtones - Free MP3 Ringtones - Free Mobile Downloads - Mobiles24.com (or "www.mobile24.com")

Trust me. u wont need more places.
or visit
Download music, movies, games, software! The Pirate Bay - The world's largest BitTorrent tracker to find Sony Ericsson related stuff

(y dont u upgrade the K800 firmware to K810?) "just a thought"