[evol]

Quick and dirty way place ffmpeg.exe into your System32 folder

C:\Windows\System32

Or your going to have to make that folder called Parky a System Variable.

Start > Right click Computer > Properties > Advanced system settings > Environment  Variables > System variables > Path > Edit

Add this

;C:\Documents and Settings\Parky\

This is for Windows 7 but XP is almost the same

Edit

I would stick the folder Parky on your C drive so it would be

;C:\Parky\