You will need to reset the Administrator Password to gain access to your profile & data.
There is free software available to do this. Look at:
PC Hell: Change Administrator Password in Windows XP/2000/Vista
I suggest you have a look at the following two descriptions on how to remove McAfee products. One is from a neutral point of view and the other by McAfee themselves.
PC Hell: How to Uninstall McAfee
How to uninstall or reinstall supported McAfee consumer products using the McAfee Consumer...
For what it's worth, the only time the battery level icon is shown on my Dell Laptop is when it's not connected to the electric power socket. Are you sure its not connected to the grid when the icon is missing??????????
If you have administrator rights, you can change any account name on this P.C. If you do not have these rights you cannot change the password protection to gain these rights. If you are not able or willing to do a re-install, I assume you do not have a OS installation disk. There is a "Forgotten...
Re: Windows 7
Got this download quite easy. It was on the boards yesterday before the U.S. got out of bed. I did a clean install on my spare rig as per advise but had a slight hiccup with my security suite (never had this with the previous builds) although they were upgrades. So far so good...