Need advice on Framework selection

[logictrap]

I have a self created CMS that uses PHP/MySQL and I want to update it to use AJAX/Javascript to improve the user interaction.

I'm looking for features such as:

• User managed Dynamic Lists with the ability to add/delete items
• Drag-n-drop items to sort them.
• Instant feedback/popup help as fields are being edited
• Is intuitive to use for someone still learning javascript

I am overwhelmed by the numerous options available and would like some advice on which frameworks to consider.

Franky I can't tell if libraries like jQuery, Mootools, Dojo, YUI are competing or complementary products.

If I use one of these do they include a framework for ajax also or is an additional library needed?

What about IDE's such as Flex, Eclipse and Echo2/3 - do these have their own libraries built in?

I know it's a lot to ask but I'd rather spend the time upfront before I naively choose something that I won't be able to use very long.

Thanks

[PremiumBlend]

I recommend jQuery. There are lots of add-ons and extensions to it. Also, they just upgraded to version 1.2.6 on the core (they've improved speed drastically since the last release). Also, version 1.5 of the UI library is out now too.

[richApps]

I also recommend jQuery. I personally prefer a light-weight framework vs. a larger toolset since I'm comfortable already with JavaScript. So your case may vary. But the elegance of jQuery (especially with the animation / style routines) and how it reduces the time it takes to produce apps is what makes me stay with it.

Some examples: http://richapps.googlepages.com/

-PF