Hi
Could you post more details about exactly what your system comprises (it's not clear if you're using Windows, Linux, OS X, etc.) and also the steps you've taken so far. For example, what did you download? What database are you trying to use, etc?
Also, you don't actually need the Apache web server in order to run Alfresco, just Tomcat on port 8080 - indeed it's often better to start from as simple a system as possible.
Finally, have you located any error logs that might contain error messages? Search for "alfresco.log"
Thanks,
Mike