One of the problems I’ve had with Ubuntu on pretty much every machine that I’ve ever put it on is that Compiz (Desktop Effects) does not run smoothly.  It’s always slightly laggy and jittery, and it’s especially noticeable when you’re moving a window around.  Fortunately, there is a fix that I discovered awhile ago that has worked every time.  The short version is that you need to install compizconfig-settings-manager and turn off the setting to auto-detect your display’s refresh rate, bump up the frame rate manually, and disable vertical sync (optional, but seems to help to).

Here’s a quick how to:

1. Open a terminal and type this command: sudo apt-get install compizconfig-settings-manager
2. Once it’s installed, run it.  It should be in the System menu if you’re using Gnome 2, or you can type “compizconfig” in the search box in Unity.  You’ll get a window like this: 
3. Click the Composite button on the top.  You should see this screen: 
4. Uncheck “Detect Refresh Rate” and set the refresh rate to 60 (or whatever you’re screen’s refresh rate is, if you know it).  It should look like this:
5. Click Back.
6. Click the OpenGL button near the top.  You should see this screen:
7. Uncheck “Sync to VBlank”.  It should look like this: 
8. Close CompizConfig-Settings-Manager and reboot your computer.  You should notice that the performance is much smoother now.