The battery thing was right on for the Acer Aspire 3000 I was working on, I noticed that using the machine in safe mode the keyboard and mouse functioned normally, and they work off and on in normal mode, but 89% off as opposed to on. When taking the panel off the bottom, because of the heat of the unit I noticed the North Bridge was extremely hot, blew out cpu fan and made sure the venting was all clear, but it would get extremely hot and I could plug in a USB Keyboard and Mouse, they would work, but the unit would not shut down (sysfader not responding). Brand NEW hard drive and fresh load. (so don't say this one's virus). Took out the battery and Voila! no problems... anymore at all. The machine is trying to charge this battery and is building up a bunch of resistance, the battery at full charge is down in 2 to 3 mins. so it's a dead cell ... or the electronics in the battery are messed up, either way the machine litterally heats up the north bridge until it is extremely hot and the keyboard and mouse just quit working properly... they're still there... just not working properly ... test it, when your mouse isn't working, give it a bit of a "tap" the mouse pointer jumps >>> ! For most just pull the battery and that will work, if that is successful then try out a new battery. Thanks for the poster(s) who helped.