If you are looking at it one project at a time, you could create a view that includes the task name, Task Actual Hours, and other columns. When you look at the Task view, you'll see the hours summed up at different levels.We have something similar in our project setup, though the names are not always consistent.
The view in the attachment shows one project. The parent task Data Delivery Team has about 200 hours reported against it and so the sum is correct at 646.
If you're interested in multiple projects, a report would be the better option, though I don't know what you'd group the tasks by
Srini