I currently run php v5.6 (build 5.6.15) and MySQL 5.14 on my local computer (Vista 32bit). And It's working perfectly.
Default Home directory D:\PHP


Now I want to install apache server 2.2.14 and PHP 5.3.
And I want to change the default home directory setting to C:\apache 2.2\htdocs\
but I want to use it separately.
for example : If I want to use debug function I will use PhpEd (use PhpEd default debug setting), if I work with html and PHP I use dreamweaver for editor.

Is OK?

I'm sorry but PhpED 5.6 does not support debugging php-5.3. You have to upgrade to version 5.8 or above.