Prescription strength stuff like Ambien or Sonata will knock you off your feet the first few times you use it. VERY powerful stuff. What's scary is you can get used to it if you take it long enough. The great thing about those though is that they only have a short burst of effectiveness before they burn off so you don't feel drowsy at all the next day. Over the counter stuff seems to take about an hour or so before I even begin to feel it and it stays with you well into the next day.
Valeran Root didn't do a thing for me personally, but seems to work for others. The hard part for me sometimes is falling asleep. Once I'm asleep I sleep soundly the whole night. I think most people who use Valeran Root like it because it seems to help them sleep more soundly. I think most sleeping pills are geared more toward helping you get to sleep rather than stay asleep (although they market them as being good for both.)