After all, a reboot seemed to fix it. The Utility Manager is memory resident, and intercepts any 'U' character and starts up. My 9 year old daughter somehow turned it on, but couldn't remember how.
I didn't think to reboot after removing it. This is one extremely irritating bit of software - I guess it is a taste of what it feels like to have to cope with a disability (the program is part of the disability suite of tools in 2000).