IIRC as soon as you enable virtual hosts, the first virtual host takes over the configuration of some of the defaults. For example ServerName and DocumentRoot get overwritten.
Just add another vhost to the beginning of your config and set the same properties as you had before:
I just had a look at your httpd.conf
as I think you want to use named virtual hosts (multiple host configurations on the same IP) you'll have to explicitly enable
and then the VirtualHost directives should look the same as in my example:
if you dont use named vhosts then anything served on a particular IP will come from the same virtual host configuration.
you might also want to have a look at the apache vhost documentation (http://httpd.apache.org/docs/current/vhosts/index.html) to get more familiar with the different concepts of name based vs. IP based vhosts and their respective advantages and drawbacks.