I installed the 64 bit version of Ubuntu 10.10 a few days ago. I had an 32 bit version installed but the new Android build requires 64 bit linux so it was time for a complete re-install. Following the re-install I found the pointer keeps halting for random amounts of time which gets really tiresome very quickly. As I had installed the proprietary nVidia drivers the first thing to do was to remove those. Unfortunately that didn't change anything so I added the XFCE desktop and booted that instead of the default Gnome one. I also tried Gnome without compiz but none of these solved the fault. I vaguely remembered having some trouble with this before so looked for kernel interrrupt issues. Some articles suggest the ACPI system can be a problem so we can reboot and add acpi=off as a boot parameter or a more restricted pnpacpi=off. This has worked fine. I've since re-enabled the current nVidia driver and the mouse has been behaving itself ever since.

The grub boot system has moved around since previous versions of ubuntu. It is no longer in /boot/grub/menu.lst but /etc/default/grub. It is quite obvious what to change and I just appended pnpacpi=off to the GRUB_CMDLINE_LINUX_DEFAULT parameter to resolve things permanently.

While I was poking about in grub2 I took the opportunity to change the grub background. The /etc/grub.d/05_debian_theme file contains options to change the background image and the colors and there is a handy grub2-splashimages package to get a few pre-made images to use.