OS X is set up as a hierarchy of folders which you can see if you double-click the hard drive icon. Some of these are:

Applications
Library
System
Users

The above folders are said to be at the root level of the drive, meaning that they are not contained within any other folders. Within them are other files and folders:

Applications contains apps that may be available to all users of the computer.
Library has folders that may apply to all users.
System contains folders that are needed to run the OS itself and you shouldn't touch anything in there unless you really know what you are doing.
Users contains a folder for each user (read "account" here). In OS X versions previous to Lion, yours has a house icon (meaning "Home"). I don't know if this has changed in Lion. Changes to a particular User account neither affect other accounts nor the folders at the root level of the drive.

If you look inside Users, you will see the name of your user account. Within your account folder, there will be a Library, which is hidden by default in Lion. To access that Library, in the Finder, Option-click the Go menu and you'll be able to access it from there (if you just click Go without holding Option, it won't be available).

Within that Library, you'll find many subfolders and you should be able to access the files that you want. I suspect that your problem in deleting items may have resulted from your being in the Library at the root of the drive. (Actually, there is a third Library as well, located in System.)

Each User should be able to add to or delete items from his/her Users folder. If you still can't do this, I suggest that you repair permissions. Follow the instructions in Mac OS X - Using Disk Utility to Repair a Disk. It won't hurt to do this and should only take a few minutes. In Snow Leopard, I get wildly inaccurate estimates of the time (like 30 minutes) but it actually takes about three. I also get lots of spurious messages that I have learned to ignore. I don't know if this has been fixed in Lion. At any rate, repairing permissions is, at worst, harmless.

When you launch System Preferences and access Users (Accounts in OS's previous to 10.7), that lets you make some changes to your User account like adding accounts, deleting accounts, changing passwords, and/or changing the type of account. We'll go into that later when you feel more comfortable with Lion.

I'm happy that you are sticking with OS X for awhile. I know that this is new to you but practice makes perfect. At one time, OS 9 was new to you and you certainly feel comfortable navigating it.



Jon

macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365