W950i Sony Ericsson Video Problems pleeeeeease help me!

Hi everyone, im a new member here, but ill skip all that and cut to the chase.
i recently purchased a sony ericsson w950i touchscreen, everything seems to be working ok apart from one thing, when i convert a movie and transfer it to the phone, it doesnt play, all i get is a black screen, but i do get the audio.
i have converted the video files in to various things to get it to work mpg4 mp4, using aac codec etc, i have tried 3gp, but nothing works works at all, just the audio when its converted into 3gp, if its anything else it defo will not work.
i would reeeeeeaaaaallly apreciate any help give on this topic.
i also tried the sony psp convert software to convert the files, and also i used a softwware called "SUPER" but still no luck.
i also have absolutely no knowlege as to what bit rate i should set it to etc frames per sec etc etc i dont know about any of that.
anybody with a w950i phone that could help would be even better, but any help at all given here will be greatly appreciated.
thanks guys hope to hear from you soon........