You don't store tap tempo. The point is you tap it, it's the speed that you're playing at. If you want set delay times - perhaps because you always play those songs at the same pace - you're using a backing track or the drummer is using a click, then you may be better actually setting the delay lengths in milliseconds rather than using the tap and note values.

It's worth investigating some basic music theory and you'll get a better understanding what is meant by dotted notes and the like. All these values in the HD aren't specific technical terms about delays, but are aspects of musical notation. Even as guitarists who often don't need to read music it's worth learning the basic principles so we can communicate with "proper" musicians.

There are quite a few other FX that use tempo settings - such as phasers, chorus and flangers. But quite often you'll want a specific sound rather than trying to match these to a tempo of a song, and in that case you'll be better off once again setting time based rather than note based values.

All of these folks have given you good and accurate advice.  I would like to maybe simplify things for you (that works best for my simple mind).  The beauty of tap tempo is this: if the drummer speeds up or slows down, or if the song gets played a little faster or slower each time you do it (which is what always happens if you don't use a click track) then you simply tap in the tempo (usually two or three taps gets it) and the device just synchronizes with that tap - and off you go in perfect time!  If the drummer speeds up or slows down during the song, just tap his new tempo in on the fly - walla - perfect timing again!  You can also tap the tempo in time with a click track if you are using one.  It makes your time based effects sound really cool. Just tap your foot to the rhythm of the song.