Administrator account in Vista Business

Just rec'd a Dell PC with Vista Business, which I read was comparable to XP
Pro. Here's a couple of observations/questions:

a) In XP Pro, you set the Administrator password during initial set-up; that
step was not in Vista Business set-up. Formerly I could logon to the XP
local PC (not the domain) as Administrator, and install/uninstall programs,
as the users have restricted rights. Now, since I haven't set the
Administrator password, I'm not able to logon to the local box as admin
(Vista says I can't because I'm part of a domain and the account is
disabled). Luckily my initial account had administrator rights, but I've got
50 PCs set-up identically with Administrator, and this capability is not
readily apparent in Vista.

b) My company has a domain (something.local). I found it rather difficult to
to join the domain (finally had to right-mouse click on My Computer >
Properties, and initiate the old wizard). Network Connections in Vista is
competely different and poorer for the changes.

Please advise, and Thanks.