I've just installed ubuntu 12.04 from a livecd. Out of curiosity, I enabled the accessibility options for people who are hard of sight. As you can guess this does the usual stuff of inverting colours, increasing text size and making the cursor larger.
Having finished the installation I booted into the new system to find accessibility mode was still installed. From the lightdm login screen I disabled this which switched colours and text size back to default, however it's only the pointer cursor that has gone back to default.
To put it another way, the "hand" icon that you get when hovering over a link, the cursor which appears when typing and pretty much every other cursor on the system are still large.
I've looked on the Universal Access menu, but there's no option to disable large cursors.
I've tried toggling accessibility on and off but to no avail.