No need to install on seperate partitions or anything. Apache is not an operating system--it's just a program that is a web server. If you want to install on a seperate partition--no problem as long as Windows can read the partition. IIS and Apache can be installed and running on the same computer at the same time. As Nikolas pointed out, both default to using port 80 of course. So either only run one at a time or configure one to run on a different port. For example, I run IIS on my home computer on port 81 as I only use it for testing stuff. I run Apache on the default port 80. Both are easy to change the port number they listen on, but I'll leave that up to you to dig around and figure out.
No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.