Possibly there were al Qaeda before March '03.
No one knows who did the UN, some al Qaeda may be part of groups who may be responsible for attacks on US forces since May. Why would we bomb the camps? They are too far from the oil fields and too few in number to pose a serious threat.
Taliban are militants, their leaders would be characterized as war lords.
We have not installed another dictator in Iraq, yet. I believe we have designated a leader in Afghanistan, but only the capital city is under firm control.
Most likely any group trying to impose stability would be as bad as Saddam was, but there is much disinformation on how bad SH was. You may find this interesting:
http://home.columbus.rr.com/lfairban/Pages/Iraq.html#HalabjahYes, we were duped by exiles like Chalabi:
http://home.columbus.rr.com/lfairban/Pages/Iraq.html#Chalabi