Zorba's is what it is - good Greek food for a great price. If you want to skip the hustle and bustle in Greektown but still get some pretty good food on a budget definitely try Zorbas.
The place isn't ever packed and is served by one slightly grumpy Greek lady so its pretty great to bring some loud kids who run around cause there's never really that many other patrons to disturb.
I always opt for the dips as appetizers, they're pretty tasty!