Below is a short report on my meagre efforts in trying to overcome the resize from minimized windows delay when using the 'Extra' effects option in Visual Effects in Ubuntu 9.04.

I have nothing new to report on this problem. I have set my Visual Effects to 'None' so that I do not have the resize delay. It was getting too annoying.
I also reinstalled Ubuntu and played around with installing/reinstalling the graphics card driver - didn't make the slightest bit of difference to the resize effect delay. I tried to follow all suggestions that I could find but, they were either too complex to follow for a mere mortal like me that is used to installing operating systems and fault finding applications (mostly in Windows, unfortunately) or the suggestions did not work...

On the plus side - I used to use Envyng to install the ATI driver for my machine but, when Jaunty came out there was not an install available from the Envy website - now there is.
Albert has made Envyng available for Ubuntu 8.04 onward and it works just fine. No more faffing about trying to follow install instructions from ATI or the Ubuntu help page (sorry guys, you do an excellent job otherwise). It was actually available in Synaptic - wow!!
Once Envy is installed you have to click on the application in the newly created 'System Tools' sub-menu to the 'Applications' menu to activate the driver then reboot. All is well.
I usually check the graphics using the Sky Rocket screensaver. I test the Appearances 'Visual Effects' setting of 'None', 'Normal' and 'Extra' and then open the screensaver settings applet to select Sky Rocket and right-away I found that I only had two choices, None or Extra. Normal would upset the Window Manager controls and even disable or freeze things forcing a reboot. On extra I had the resize delay from minimized windows but, on None I have no problems. My screensaver runs well and no other visual problems at all. In fact the system runs fast with None selected. I do not need the Extra effects even if they do look pretty. I would keep them if the delay bug was not prsent as I like being able to swap desktops using the cube but, the delay is just too damn annoying as I said.
Phew!! well hope someone enjoys reading this. If anyone knows of an alternative to Compiz it might prove interesting...
Cheers for now.