Hi, I have a DELL Inspiron 1100 laptop with Intel 845G Graphic Card running Ubuntu 7.10 smoothly with a lot of desktop effect, unfortunately, 7.10 is no more supported and I need to get a newest supported release.
I brought 9.10 yesterday, and ran it on LiveCD, but when I go to enable Desktop Effects I get a message telling me that it could not be enabled. I think this problem is similar to the problem in 9.04 but I've heard that it has been fixed.
So, how can I enable Compiz Effects on Ubuntu 9.10 with Intel 845G Video card???

have you asked this question on the ubuntuforums?

Installing this package through Synaptic fixed it for me:

xserver-xorg-video-intel

Installing it automatically removed "xserver-xorg-video-intel-2.4"

Hope this helps

I have the same/similar problem with a Dell dimension. The screen resolution is fixed at 800x600, under 9.04 it worked fine at 1024x768. Under Jaunty I used a package called 915resolution, which fixed the problem. Under 9.10 it is NOT in the repositories.If you find any workarounds to get that package please post them. Thanks
robrist

You can try using xrandr as is discussed in this tutorial:
https://wiki.ubuntu.com/X/Troubleshooting/Resolution