On Wednesday 03 October 2007, Daniel B. Thurman wrote:
> Platform: Windows 2000 Server
>
> Is there some way to ensure PostgreSQL starts first before starting
> Slony service?

I've little experience with that OS, but the first google hit for "windows 
service dependencies" seems to be what you  are looking for:
http://support.microsoft.com/kb/193888

Have fun,
  Steve.