For what it's worth, I went into the package manager and searched for, 'mouse'. After that, I clicked on all the already installed applications (there aren't that many) and reinstalled all of 'em. Then I searched for 'keyboard' and did the same thing. Not much change there, either. Finally, I searched for 'input' and found a file called, 'inputattach'. Reinstalled it and my mouse problems are solved. Works like it did on the day I installed 10.04. It's so nice to have a mouse that behaves itself and works like it should, again.
I'm a relatively new Ubuntu user, but instead of asking a lot of questions and then waiting for someone to reply and jump through a lot of hoops trying the workarounds and suggestions, I decided to try and do something about it on my own, and managed to solve my mouse problems (computer mouse, that is...;)
What the file 'inputattach' re-installation cleared up, was the need to click several times to open up a folder, having to hold the button down for sometimes as long as three or four seconds before the click would be activated, or having to right click to open a folder or open a file with a particular application.
Just wanted to share this with you since the 'input' of my mouse now seems to once again, be completely and fully 're-attached' to my computer's OS.