I have just written a blog showing exactly what you need (how you can get a report on history in chronological order, regardless of contact). This leverages he fact that ACT! Groups will consolidate history and notes for all contacts in the group. So, by creating a group that includes ALL your contacts, you can run a group report that shows you the history chronologically. The blog includes an actual customized report file as an example.
I wanted to thank you for your clear and practical post regarding the reporting issues. In the report mentioned above, I needed to also list the company name since after 40-60 calls a day my trainer does not know which contact goes with what company. I am new to ACT, I was wondering if there was any document that explained how act works with regard to reporting, a reporting 101 type. This way I could learn "how to fish" and even contribute to the group.