ANDREW BALTAZAR

Medill News Service

It was supposed to be on home computers more than three years ago. But after numerous delays and redesigns, Windows Vista, Microsoft's newest version of the Windows operating system, will finally be on store shelves today.

More than five years in the making, Vista was released for businesses Nov. 30. Vista retails for $100 to $400, depending on the version and whether the user is upgrading from Windows XP.

Over the weekend, Dell Inc. started taking orders for PCs with Vista for delivery Tuesday and beyond. Kevin Rollins, Dell's chief executive, said at a launch event Monday that the company's Web site saw a 20 percent jump in traffic and that "tens of thousands of copies" of Vista were sold.

Vista offers a number of improvements over its popular older sibling, Windows XP, according to Joe Ryan, owner of Chicago Computer Repair in Evanston. It has a new quick-search function that instantly shows you files you're looking for.

It has built-in spyware protection. Best of all, it's easy to use and has an eye-catching user interface called "Aero," which can display 3D effects and animations in open windows.

Even with these "neat" features, Ryan said, casual computer users should wait about a year before upgrading to Microsoft's latest and greatest.

"Right now, there aren't very many advantages to upgrading to Vista, and that's because it's too new," said Ryan, who has tested Vista at his computer shop.

"It's the same when any operating system comes out; they need to work the bugs out."

In addition, users will need a fairly new computer with Intel's Core Duo processor and at least 1 gigabyte of memory to run Vista smoothly, according to Ryan. Microsoft's Web site says Vista will work on older computers with at least an 800 megahertz processor and 512 megabytes of memory, but the eye-catching interface will be switched off.

"As long as you have the new hardware, you're going to be okay," Ryan said.

"But if you still have a first, second or even third generation Pentium 4 processor, you're going to have problems."

Another problem that could plague Vista is Microsoft's heavy reliance on third-party vendors to support hardware and software, said Kristina Dorado, 24, an information technology administrator in Chicago.

"When it comes to Windows, you have to depend on other vendors to fix whatever the problem is," she said.

As a result, said Ryan, third-party hardware components like sound, graphics and network cards older than a few months may not work because their accompanying software was not designed for the new operating system. Also, a number of software applications are not yet compatible with Vista.

Still, Ryan likes Vista and thinks most Windows users will own it within one to two years, after early adopters pinpoint major glitches and Microsoft produces software updates and fixes. He described the experience of using Vista as simple and fun.

"For the majority of end users, that's what they're looking for. It's innovative, it's new, it's sharp. It looks really neat, it looks high-tech. It looks like something out of science fiction."

One such user-friendly feature from the Aero interface spreads out your windows and tilts them so you can see each one's content. Vista also displays what's inside minimized applications if you run the mouse cursor along the taskbar.

Another new feature is "Desktop Gadgets," a collection of specialized mini applications, Ryan said.

"It's a little, active icon where you can see your weather, your sport scores, your time, whatever you want. It's on the desktop so you don't have to click on anything to go to it."

To users of Apple's Mac OS X operating system, many of Vista's features are old news. Momoko Fritz, Mac specialist at the N. Michigan Avenue Apple Store, said OS X has had its own version of "Desktop Gadgets," 3D windows flipping and instant searching for at least a year.

"The main difference between Vista and OS X is the dock," Fritz said, referring to OS X's row of software icons at the bottom of the screen, which makes it easy to open files. "You're one click away from your applications."

Fritz also said she wouldn't use Vista unless Microsoft solves Windows' virus and spyware problems.

Vista will come in a variety of flavors, including "Home Basic," "Home Premium" and "Ultimate," with "Ultimate" having the largest feature set. Ryan said "Home Basic," the least expensive of the three, should be adequate for most casual computer users. But if they want the "Aero" visual effects, they have to purchase one of the other two versions.

The Associated Press contributed to this report.