I wish to convert a running joomla 1. based website into joomla 1.5 based site.

For design i'll choose worthwhile 1.5 template but exactly how i'm able to import 1. databse into 1.5 site's databse. my new joomla 1.5 site may have different url than old 1. joomla site.

I wish to convert whole things of old 1. site to at least one.5 site

Now you ask ,, the number of extension, components, plug ins are you currently using and it is your joomla install clean or compromised? The Joomla Documentations have step-by-step recommendations regarding how to migrate from 1. to at least one.5 there even is really a migration manager/assistant.

For those who have a non-compromised version, you need to follow these instructions:

Joomla Migration

For those who have a compromised version as well as an upgrade does not work (check it out), then you'll have to write your personal migration scripts.