Version 4.4 is the latest and version 4.3.10 is the version on the Slackware site. I personually use the Slackware version and have had no problems with it.
To make it work with apache, you need to edit the /etc/apache/httpd.conf file. At the very end there is a php section. Uncomment the line that says:
Include /etc/apache/mod_php.conf
When you do the configure, you'll need to include things that you want to use with it, like mysql and such. I do not know if you looked at this
http://www.php.net/manual/en/install.unix.php , but the first comment at the end has an examples on configuring.
I would say this would work for you.
./configure --with-apxs=/usr/sbin/apxs --with-mysql=/usr/share --with-openssl --with-zlib --enable-exif --with-gd
You might have to play around with it a little though and include or exclude things.