Yep, Apache is a great base for mixed applications. That's what I usually do: Apache in the front, parts built on mod_perl or cgi, parts built on Zope (via mod_proxy and mod_rewrite behind the Apache) and parts with event based rendering that result in static HTML stuff.
Ok, with high traffic systems I usually have a bit more than just one Zope behind the Apache. Actually it's more like two Apache machines with load balancer in front, 4 Zope machines in the back, connected via a Zeo server, a PostgreSQL machine (with a spare one for failover) in the back. Several servers around all that to connect it and hold it together (for example two machines running load balancers to match up between two Apaches and 4 Zopes). But it's a system with 2500 hits per minute in it's prime time, 1000 hits alone to the Zope application parts. Each Zope page with 3-4 SQL statements. :-)
Mixing static and dynamic parts is essential with this system.
The main problem with really high performance systems that make use of event based rendering is how to build a really fast replicating filesystem. If you create a comment, the comment stuff should go to the background to some rendering machine, be rendered there into static pages that are pushed back to the front machines. That needs to be performant, if you do that wrong, your system will be blocked by shuffling files around :-)