I used to have an eTrex Summit, which is like the Vista except for not having maps. I did remember displaying "Total Ascent" as well as "Total Decent" on the altitude page, but right now I can't remember how to.
On my presently owned Legend, which has maps like the Vista, but no altitude, you can change the data variables by moving the cursor to the data field and press "enter". A list of data fields is then displayed. Chose which field you want and press "enter".
If that doesn't work, you can e-mail the Garmin technical support off of the Garmin webpage and they will answer your question (they have great customer service).
BTW, I also presently own a Garmin GPSMAP 60CS and I do have it set up to display "Total Ascent" and "Total Descent".
This message was edited by sglum on 1-19-06 @ 2:14 PM