Yes, you can do that sort of thing in Task Scheduler quite easily, although the UI on Task Scheduler will take some learning.
I am familiar with the Task Scheduler UI, including the nasty bit where if you change your login password (as required periodically by many employers) all the tasks you set up cease to work until you go back through and re-do them.

The program I linked to at the top of this thread does pretty much exactly what I want, other than the dual-time thing (I just set it to 30 minutes regardless) and no audio.
tanstaafl.