Although he says KDE is too simple yet being a Gnome me self :P... I still find KDE4 to be quite elegant and full of useful features. Anyhow all I'm trying to say is that, you hardly see an application which is pretty simple with Qt or from KDE developers in general.
No matter what they design... you'll get a lot of options to play with. It's apparent with players such as VLC (written in Qt), UMPlayer, or anything that has the KDE touch.
Yet if you were looking for a simple and fast multimedia player which uses the KDE's own multimedia framework called Phonon... then Dragon Player is the one to go for.
*. Anything Phonon plays... the Dragon can play :) - MP3, MP4, OGM, MKV... anything goes.
*. Resuming capability (starts the videos from the last position you exit the player).
*. Automatic subtitle loading.
*. Change screen brightness/hue/contrast.
*. CD/DVD playback support.
*. Speed - Yes, this is one of the things you'll get with an application that is simple. It loads fast and known to take, somewhat less system resources in comparison with others.
Anyway, you can install Dragon Player in Ubuntu 11.04 Natty Narwhal or 10.10 and 10.04 by entering the below command.
sudo apt-get install dragonplayerRemember, unless you're using Kubuntu or KDE desktop, this will require some decent amount of file size downloading (about 64MB). Although this has nothing to do with the player, it's just that, since it's KDE based and you're using Gnome, there has to be some KDE bindings installed first. That' all I've gotta say about it :). Enjoy.