awr report shows high db time

Our db version is 10.2.0.3

Yesterday we experienced very slowness. I ran the awr report today and indeed for one hour snapshot time period, it is showing db time 667.48 mins. Below is the stats and top 5 timed events. Gurus, please point me to the right direction as to well should I look into solving the issue? Thank you very much.

              Snap Id      Snap Time      Sessions Curs/Sess
            --------- ------------------- -------- ---------
Begin Snap:     43727 22-Jan-14 14:00:55     2,940      23.1
  End Snap:     43728 22-Jan-14 15:00:36     2,954      23.4
   Elapsed:               59.68 (mins)
   DB Time:              667.48 (mins)

Cache Sizes
~~~~~~~~~~~                       Begin        End
                             ---------- ----------
               Buffer Cache:        96M        96M  Std Block Size:         8K
           Shared Pool Size:       832M       832M      Log Buffer:    14,400K