Knowing how you'll use your computer will help you determine what type of minimum requirements the computer needs to have. Keep in mind that the size of the software you plan to run will dictate how much memory your computer should have. Consider how you will use your computer, then ask about the software you'll need. Typically, you'll need a minimum of 32 MB of memory to adequately run most programs. If you will be using more than one program at a time, you should probably get more.
Most computer systems come with preloaded software.
Be sure to check the inventory of what's on the computer, so you know what you're getting. A good software offer can make a big difference in the final price of your computer. You may be able to purchase additional software when you buy your computer, preloaded, at significantly less than if you bought the software separately. With computers, it's a good rule of thumb to buy as much as you can afford. You might want to hold off buying any software until you've had a chance to take a look at the software which comes with your new computer.