Hi ckangell.
That all sounds achievable: your first port of call should be our Themer’s Guide which explains much of the basics.
Prevent user from being directed to events page when they click on
The events are linked to from within the month/single-event.php template … you could simply strip out the <a> link elements that surround the event title.
Display the tooltip onclick rather than on mouseenter
So you’d need to write some custom JS to do this, either building on and working around the existing code or else you could, potentially, dequeue our own Javascript first (however you would lose other client-side behaviours in the process).