First of all you would need a software....
Mediacoder,Google it and download.its free

Now the Setting for your Cell phone
Open the sofware and select a video you want to convert

Then do the following settings for 320x240 Resolution Cell phones

NOTE:Bitrate 400 is the minimum bitrate which I think would run on all cell phones without hiccups.
Nokia Symbian can run a video of Bitrate 700 withoit hiccups
Therefore to increase the quality you can experiment with this bitrate by increasing it but 400 is the minimum which has respectable quality and runs on most cell phones without lags

The Container Can be changed to MP4 also,but it makes no diffrence.

and Leave all the tabs as they are.

and Convert the video!

For 640x360(Nokia 5800 and N97)

Any bitrate higher than 800 would cause the video to lag on Nokia 5800
Dont know about N97

The Container can be changed from MP4 to 3GP
Doesnt make any diffrence

For *.MKV Files you would have to change the Settings in Sounds tab
Change the Channels from ORIGINAL to STEREO
otherwise the sound wont work

Also,The Cropper tool in the Picture tab can be used to crop the video to your demands(Like Removing the Black Color on top and bottom of DVDs)

This is my First Tutorial...

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