Need admin access on my system

I have a Windows 7 Pro SP1 machine with a couple accounts on it. both are restricted accounts and I have no idea how to get an account with administrator rights. when I login and goto User Accounts in the control panel and try to manage the accounts or do anything at all such as update Java the machine will always prompt me with "Do you want to allow the following program to make changes to this computer?" as shown in the attached screenshot.

Does anyone know how to fix or get by this? I have no idea what the administrator password is or even what the username is. When I do a "net user" at the cmd prompt I see:

C:\>net user
User accounts for \\ADM-RECEPTION
---------------------------------------------------------
Admin Administrator Guest
The command completed successfully.

Are these network accounts or local machine accounts? I never login as Admin or Administrator. The Administrator account is disabled, but I don't have the rights to enable it. See the second screenshot.

Any idea what the best move is?

yes, its a PC from work. there is no domain anymore though. the domain server (Windows Server 2008) was decommissioned. I just need to know how to get administrator access on this machine if I don't have any password...

Kaktussoft said:

How are you logged on now? as user admin, administrator or guest?

I login as a normal user called "newstudent". I don't understand this stuff, how can I login with "newstudent" or another used called "nhart" if there is no domain server available.

THe only two acounts that I can login with are the newstudent and nhart and both are not admin accounts. I need to make them admin accounts I guess but don't have the password. is it possible you think?