Convert Current PHP/MySQL site to new platform

Check out my site at [login to view URL] and scroll down to the bottom to see the Powered by link at the bottom. I would like to convert my site from this current script to a new one. The current script is completely encoded and therefore makes any modifications impossible (I wish I would have known it was encoded before I purchased the script). I would like to switch to a new script which is not encoded and would like to transfer all the information in the MySQL databases to the new site. The current site is based on an article directory script and the wording has just been changed to apply to the whole story submission concept. I would like a script that is more oriented to the story submission idea and not an article directory script. All the current stories and user information will have to be able to transfer to the new site. I want a script where I can completely change the layout and modules. I would like a script with better search capabilities and submission functions. If anyone has any suggestions or wants to work on this project let me know! Thanks.