Need help understanding Win7 accounts hierarchy

~~Little Old Lady Needs Help Crossing The Windows Street~~
This is probably on the board somewhere but I can't seem to find it.
I'm used to running my pcs under the single user (before Windows was able to do multiple user accounts) or Owner accounts. I'm the only one who ever uses my pcs. What I'm having a little trouble with is understanding Win7 and accounts. I know there's a hidden adminstrator account and until I understand why I'm not messing with that one. I know how to take ownership of folders and files so I can get into nearly everything on the pc, but I have those still set at the defaults until I understand how to give myself total permission everywhere without opening the door for everyone else (net security, not other users) to be able to get into everything too. I have what's apparently the standard Administrator/User account that gets set up when you first boot up a new laptop. When I was checking into taking ownership of files and folders, I saw 2 adminstrator accounts with my pc name (1: Administrator/PC Name, 2: Administrators/Same PC Name) and 1 account with my user name. Plus the System account. The only account I know of setting up was the first boot up "Give a user name, Give a PC name" thing.
I've been reading the suggestion about creating a user account just to be on the net with and using the adminstrator account for installing updates, etc (which leads me to wonder if I can partition a small part of the hard drive to make a specific user account just for that purpose alone). The Win7 Adminstrator/User account isn't acting like what I'm used to because I've tried a few things and it asked me if I want to take permanent ownership of certain folders, or did I want to run certain things as an administrator, etc. To me it's acting more like a User account than an administrator account.
I haven't taken the laptop online yet because I want to know if I take a user account online and get all the updates (my first netstop) and then an anti-virus in place, will that cover all accounts or do I need to use the administrator account for that...
Sorry if this is a bit confusing but I'm confused. I'm trying to figure out how to set up basic security on the thing before I go running around in the wild with it. I don't know if I should make the User account first or do updates/anti-virus first.....
Basically all I've done with the laptop is make the recovery discs, putz with a few safe settings, made a restore point. I've ventured into the folder/file ownership thing but then took it back to the restore point and checked to see everything was back to what it was before I did those things.
My last 2 pcs had Windows XP, before that my pc had Windows 95, my 1st experience was DOS (1. something or other) and BASIC. I'm used to digging all over my pcs: registry, settings, etc and inside them: replacing drives, cables, adding slave drives and externals, minimal pc repair type stuff but not power supplies, motherboards, etc. I'm very comfortable with line commands (actually more comfortable with those than gui).
Sorry if this is a bit long but one of the threads (the Welcome thread I think but don't hold me to that) said to mention your pc experience. (Just for anyone curious, the 1st computer I owned was a TRS-80.)
Thanks in advance for any help offered here.

First up, there are only 2 normal accounts for 7 - standard and Admin Approval Mode/Administrator. You run in Admin Approval Mode in the default Admin account until UAC elevates you with full admin privileges, depending on what you install or run. I would run in the standard admin account and only use that one for yourself, standard accounts for anyone else. Type UAC in the start menu and then drag the slider all the way up to maximize one aspect of your security, otherwise UAC may be spoofed at its defaults. This architecture can never be replicated in XP, and is why XP is more insecure than 7. 7 also virtualizes some registry keys and folders for older non-UAC programs but you don't need to know about that yet.

Install chipset drivers first, then other drivers, then antivirus, then windows updates. The hidden admin account has no limitations and you won't really need anyway. Also, never ever use take ownership on any system folders, only your own, and only if you have to. Also, don't pay for antivirus, use Microsoft Security Essentials or AVG Anti-Virus Free (just don't install the link checker).

This REALLY simplified the steps to help me set the laptop up right. I'm glad I read this before heading off to the library hotspot to get the updates first.
I made a system repair disc this morning and I'm going to dig for the info on how to make a system image after I get the steps you outlined in place and it looks like it's all working well together.
Have a nice day!

I bookmarked the thread for later perusal.
I totally agree about storing the image on a separate drive. I wonder if it can be archived to a disc though. My guess is probably not due to the size.
I'm on a huge learning curve here because basically I didn't run much security on my desktops. All I have running on this desktop is the firewall. I haven't had good experiences with the AVs I've tried. I'm sure that's more due to my errors than the programs themselves. I've just had better luck not running an AV and using 4-5 online scanners.
My thinking is that since Win7 is still fairly new where the 1st sp pack hasn't been put out yet that it's going to be a major target for the sort of folks who like to wreck havoc on the net and it's long past time I learned some pc security. (Plus this will be my 1st machine that may actually have the resources to run the stuff.)
I really thank everyone on the board for putting up the information they have. If I listed all the things that have helped me just in the last few days this will be a very long post. I even had to relearn how to make screenshots and after a half hour trying and digging through the laptop's help and support section, I ended up finding the answer here in the tutorial section.
I still have a brazillion questions but I'm trying to take it a step at a time.