your issue is exactly where Joe pointed you to.
an Event is a single element
an Alert can be seen as a higher level object, that could be made up from multiple Events (which are tied together because they have a common attribute: e.g they come from the same "managed Object")
what is written in the Details on the Notification Mib:
http://www.cisco.com/en/US/partner/products/sw/cscowork/ps2421/products_user_guide_chapter09186a0080702b52.html
[...]
The Management application computes events for a device via
polling snmp mib objects on the device and/or by listening to
SNMP Traps. Multiple events on a single device roll up into what
is called an Alert - there can be only one alert for a given
device at any given time.
[...]
And with the following info from the user guide:
http://www.cisco.com/en/US/partner/products/sw/cscowork/ps2421/products_user_guide_chapter09186a0080702bc5.html#wp1073777
-> read the note below Step3:
"Events and alerts are not mutually exclusive [...]"
So I think you want to be notified for events rather then alerts. Look at the pics you posted: the second pic shows a check mark for 'Alerts Severity: Critical' and 'Alerts Status: Active';
look at your mail, you receive an email for an ALERT with Alert Severity: CRITICAL and Alert Status: ACTIVE; The managed object type is Router, I cant see it in pic.2 but I assume you added this device (161.144.100.2) to the Notification group.
This is what you have configured. Remove the check marks from the 'Alert Severity' and 'Alert Status' fields for this Notification Group and you should get what you want (mail on a specific event and not for an alert from the device)