Try another media player. This looks more like an issue on the playback part. Since you used the default lossless module, chances are slim it could be anything in AE. It doesn't use OpenGL or any such thing which normally cause such buffer artifacts.
Thank you for your help.. You were right, for some reason the a defalt player would open to play it, it was a player from something i downloaded, i used quick time and its working well.
What would be the best setting to get the best render?
thank you again..
Well, the question is what you plan to do with your footage. If you plan on working with it further, visually lossles compression is a must in most situations, to avoid artifacts from re-compressing over and over. That doesn't mean you need to use binary lossless compression such as the default render module, though. CoDecs like Quicktime Animation or PNG can do that quite well and reduce file size without losing image info. generally Quicktime offers many more options than AVI, so I recommend you settle for that for intermediates. For final delivery, anything can be used and in case of DVD, BluRay, WMV, H.264 and Flash, you will have to follow the specifications of these formats, anyway, which means you have to use certain resolutions to get good compression. Unfortunately it's a very complex topic, so as a start, you should read the respective help section to get at least a feel for when to use what. It has a number of links to external sites that provide soem useful workflow guides, especially for finding good compression settings. if you give us more detailed info, we can provide some kick-start tips and step by step instructions.