I've never had any luck with the httpd if it throws any errors regardless of if it reports it only as being a runtime related one. I'd uninstall that first with
httpd.exe -k uninstall, then configure the httpd.conf. You need to change the document root and the server software installation; I can't recall the actual names, but they are fairly clear and I believe are within the first few directives of the httpd.conf.
PHP.ini doesn't technically need modifications to run, but you typically configure it for extensions and on windows systems you'll want to configure the session and temporary directories.
Once apache is working then you can configure the PHP module for it.
I can't tell you if wamp takes longer than this or not. I've seen threads here that indicate its not configured by default either for php (which is IMO very unusual given its name and purpose). I always install separately since it lets me change individual software pieces to different versions.
Language installation is never a problem. PHP is simply unzipped (don't get the msi's that's a waste), python is a simple install as is perl. I can't remember when I last used ruby if it was troublesome to install, but if I don't remember than usually that's a good sign.