if you hate your computer...

Microsoft Windows is the problem

There is probably little reason to buy a new one. Unless the hardware is old or not powerful enough for what you're looking to do you won't need a new computer. The problem is the Microsoft Windows (1985) operating system. The solution is to use a different operating system.

What else is there?

Other operating systems include the almost endless distributions of Linux (1991), various distributions of BSD (1977), and the Macintosh OS X (2001, you'll have to buy a Macintosh of course). A majority of the Linux distributions are actually free to download and use, and the same goes for its software. Linux, BSD, OS X are all based on the UNIX operating system which has been in use since the 1970s.

Windows security (see oxymoron)

The lack of security for Windows is its downfall. Microsoft would have to rebuild Windows from the ground up in order to fix this problem. Each new version of Windows is typically built based off of previous versions.

The two fundamental versions of Windows started with Windows 3.1 and Windows NT.

Windows 3.1

1. Windows 95 was similar to Windows 3.1 in that is was not a true operating system, but more like a desktop environment run under DOS 6.22. Visually similar to OS/2's Workplace Shell
2. Windows 98 is Windows 95 + 3. Same thing, different year.
3. Windows ME is a tweaked/bastardized Windows 98.

Windows NT

1. Windows 2000 was built from Windows NT and incorporates the Windows 95 look.
2. Windows XP is Windows 2000 with a candy coating and aimed for the average user.
3. Windows Vista is Windows XP with more eye-candy and a bigger hunger for hardware.
4. Windows 7 is Windows Vista with the major bugs worked out and slightly different eye candy.

Windows: the virus magnet

There are over 60,000 viruses for Microsoft Windows vs around 40 for OS X and Linux. These 40 viruses are confined to laboratory study and do not run wild on the internet unlike the 60,000 for Windows. Newcomers to Linux often ask where they can find anti-virus programs only to be told there really aren't any. The few anti-virus programs available are typically for the server environment to squash Windows viruses before they make their way onto a network with Windows machine.

Linux can be easy

Linux may be more difficult for the computer illiterate, but with a desktop environment (e.g. KDE or Gnome) almost anyone can use a Linux system just as easily as Windows.