Originally Posted by m2azer
my question how would I know that the options I selected to configure both apache & php with are the most common/optimum/best setup
The beauty of manual compilation is that you can customize the configure switches you need and leave out the ones you don't need. So selecting the options that defines/suits your environment is the best/optimum setup for you. The other reason to manually strip down unnecessary dependencies is to eliminate an attack vector if say package X gets compromised. Since you didn't compile php or apache against package X, you are relatively safe.
I don't think you need to be software programmer to decipher the configure options. Some options may be arguably harder to understand but the official documentation or a google search will give you good hints.
Apache documentation, especially, is good at documenting what each module does. Alternatively, you can compile all apache modules and then only use the one you need in httpd.conf.
If you want to check out php options, good place to look is the slackbuild script for php in Slackware. Check the url below.
That should give you a nice set of configure switches.