Redmine

Hi all, im new to this forum and i must say this software looks very capable.

I want to setup a website where a team of developers (distributed all over the world) can get together and develop Software.

So far (after a ton of reading) im coming close to the conclusion that the tools I will need are:
a Version control system (git , mercurial), a bugtracker and and project manager? redmine seems to have all of this, is there anything else I might need?.

Now my questions are:
- Am I correct and what other tools will I need?
- Will is be possible to integrate these tools with my website? by this I mean the look ( my website logo) and feel (not having to bounce around from one link to another, keeping it all on one domain)? -
I would also prefer hosting my own git/mercurial repo as i dont want to have to go open source , now does installing redmine mean I can now host my own repo?

Also another question, I am from a php back ground and the site im developing is PHP, but i noticed redmine is Ruby, will it be possible to mix it with PHP site,maybe on different subdomain?.