Is that the above method is difficult.just follow the steps..this doesn't require u to know the admin password but still u can change it..
Start >> Run >> [type]cmd // this will open your command prompt
[type] net(space)user(press enter)
[type] net(space)user(space)[windowsloginid](sp ace)*(press enter)
// for e.g. : net user HOME *(press enter)
[type] new password (press enter) and retype it (press enter).. it will show u confirmation... // caution it wont show u the password u type.. but it still types.. the blinking pointer will b there at the same place.. but it still works..