After downloading it, launch the installer. Follow the prompts, and complete the install.
Next, let's get a copy of Ubuntu. Although there are newer versions, I'd recommend that you start with the most recent "long-term support" (LTS) version, which as of this writing is version 12.04 LTS. Actually, next month, 14.04 LTS should be coming out, but we'll see if it's good and stable like 12.04. I expect it will be.
You can get Ubuntu Desktop, which includes a GUI, or you can get Ubuntu Server, which is text only. If you're just learning Linux, I'd suggest that you install the desktop version, as the GUI can be helpful for newbies. You can do all the server stuff with a desktop anyway. You can download Ubuntu Desktop at http://www.ubuntu.com/download/desktop. Select version 12.04 LTS. Choose the 64-bit version if you are running a 64-bit version of Windows, otherwise choose the 32-bit version.
Once the download is finished, launch VMware Player.
Now, click on "Create a New Virtual Machine. In the next screen, select "Installer Disc Image File (ISO)", and browse to the Ubuntu ISO image you downloaded. Player should detect Ubuntu on the ISO and suggest the "Easy Install" mode as shown here.
Sounds great, let's do that. Click Next, and Player will prompt you for a username and password to setup in Ubuntu.
On the next screen, you will specify a name for the VM, and the path to store the VM's files. The screen after that shows the virtual disk configuration. The defaults are advisable, and don't worry, Player doesn't use all of the space all at once. Space is consumed as data is written. So even though the default is a 20 GB disk for Ubuntu, it will likely only take up around 3 GB once Ubuntu is installed.
Next, at the summary page, click the "Customize Hardware" button. Have a look at the memory configuration. 1 GB of RAM should be enough. Increasing the amount of RAM given to the VM doesn't hurt, unless your PC doesn't have it to give, in which case your PC will start to swap like mad while the VM is running, and performance will be horrible. If you're tight on RAM, you can reduce the amount to say, 768 MB. That's still enough to run Ubuntu. Even 512 would do in a pinch.
Next, click on the Processors item. I would recommend giving the VM four CPUs (if you have that many). Two might be enough if you have a fast CPU, but I find that on my I-5 processor, 2 is a little under powered. Note that I have an I-5 Gen 1, which really only has two cores in it, but hyperthreading is enabled, so I see 4.
Go ahead and Download it while the install is running. VMware Tools will be installed in Ubuntu and help things run a bit smoother, like resizing the desktop when you resize the VM's window. Meanwhile, you will see the Ubuntu installer doing its thing.
After the installer completes, the VM will reboot and VMware Tools will be installed in the VM. When that's done, Ubuntu will finish booting and bring you to the login screen.
Enter the password that you specified earlier, and press enter. Congratulations, you've logged into your brand new virtual Ubuntu desktop. What you're looking at is Ubuntu's Unity desktop. There's an icon bar on the left side of the screen. That top icon is like the Windows start button. If you click it, you can access all of the programs that have icons on the machine. The text box allows you to type the name of a program and it will find icons that match the letters as you type. Let's type term to find the terminal application.
Click on the Terminal icon and the terminal will open. The first thing we want to do is get all the patches up to date, so we can be as secure and bug free as possible. In the terminal, type the following commands:
sudo apt-get update
(you will be prompted for your password). Then type:
sudo apt-get dist-upgrade
When prompted, answer Y to proceed with the updates. It should take a few minutes. After the updates are complete it's advisable to reboot and login again. Type:
After the reboot and you've logged in again, you can go about the business of falling in love with Ubuntu. A few more tips. You will find an icon that looks like a shopping bag. That's the Software Center. Launch it and have a look around. There's a huge amount of free software available to install. Ubuntu comes with the Firefox web browser by default, but if you're a Chrome fan, you can find it in Software Center (it's called chromium). Or you can install it via the terminal by typing:
sudo apt-get install chromium-browser
Last tip. I'm not a big fan of the Unity desktop. I much prefer the Gnome desktop. To install it, type:
sudo apt-get install gnome-shell
After it's installed, logout (via that gear icon in the upper right corner of the screen). At the login screen, click the little Ubuntu icon next to your name, and select the gnome icon instead (the foot). Enter your password and you will be in the Gnome interface. To switch back to Unity, logout, select the Ubuntu icon, you get the idea.
Hope you enjoy it!