After nearly seven years of false starts, revisions and delays, Windows Vista makes its much-anticipated public retail debut Jan. 30.

But is this successor to Microsoft's much-maligned XP operating system worth the wait? Before you answer, check out the specs of your desktop or laptop computer and be prepared to spend - a lot.

It will cost you a minimum of $99.95 to upgrade from XP to Vista's Home Basic ($199 for the full version), the cheapest of Vista's four retail editions. From there, the releases are as progressively more expensive as they are feature-laden. Home Premium (which probably will be the most popular with users) will retail for $239 ($159 to upgrade), the Business-level version fetches $299 ($199) and then there's Vista Ultimate, at $399 ($259), containing all of the hundreds of improvements and additions nearly seven years of work have produced.

"This is really the best Windows experience our customers will have ever had," said Peter McKiernan, Microsoft's senior product manager. "Vista is the most-tested operating system we've ever released. . . . We've been quality-driven."

Don't close your wallet just yet. To plumb the depths of Vista's unarguable beauty and functionality, you probably will need an upgrade, or perhaps a new system entirely.

Although Microsoft suggests that even a comparatively dated machine with a 800-megahertz processor and 512 megabytes of RAM is "premium ready," or can run Vista, the techs at Microsoft's Redmond, Wash., headquarters must have had their tongues firmly planted in cheek when they came up with that.

Vista will run on such a machine, if by "run" you mean excruciatingly slow, and with mostly minimal features. Better to stick with XP, which Microsoft will continue to support for years. Or try Linux, if you want a different look without the cost of hardware upgrades and don't mind learning the ins and outs of a new OS.

As The Tribune's high-tech reporter, I ran Vista on my own aging desktop and initially found it sluggish and prone to freeze-ups, even with a 1.6 GHz processor and 1 GB of RAM on board - well above system recommendations. It took about $200 in RAM and graphics-card upgrades before my Compaq machine could adequately sample Vista's wares.

Finally, I could see the new, eye-popping Windows Aero graphics, replete with sharp, rich colors and animation. Vista also had incorporated a suite of multimedia tools meshing production and organization of music, photographs and video. And it has simplified use of its system-maintenance accessories.

It was with Vista's desktop interface that deja vu set in. Although appreciating the massive redesign, I recognized more than a few concepts borrowed from Microsoft's competitors, Apple OS X Tiger and Linux.

Vista offers a see-through Sidebar, a panel offering "gadgets" - downloadable weather, games, sticky note and other applications similar to the "widgets" long offered by Apple on its translucent "Dashboard" column. And like OS X, Vista has a built-in calendar, not unlike Apple's standard "iCal" feature.

Familiar, too, is the look of Vista's Aero, a visual cousin of OS X's Aqua interface, as well as graphical schemes offered in Novell Suse Linux Enterprise 10.2 and Ubuntu, the top two Linux distributions.

For about $129, OS X runs fine on a Mac Mini, an entry-level Apple system with a 1.66 GHz processor, 512 MB RAM and 64 MHz graphics module. Linux offers free versions that work well even on systems with as little as a 400 MHz processor and 128 MB of RAM.

Where Microsoft has made mammoth efforts is in tightening security. Hoping to end the seemingly endless stream of patches and updates that plagued XP, Vista's programmers have integrated security applications that run constantly in the background to foil spam, spyware, viruses, fraudulent Web sites and identity-stealing hackers.

That's a lot of demand on processing power, but Vista's creators have countered with some nifty performance enhancers. SuperFetch monitors program access history, preloading favorites as it learns your use patterns. ReadyDrive works with newer, hybrid hard drives with onboard flash memory to speed program transitions.

My favorite? ReadyBoost, the way for we poorer geeks to bump up performance with relatively cheap forms of flash memory, from thumb drives to the memory sticks and cards used in digital cameras, PDAs, cell phones and media players.

In my case, ReadyBoost alerted when I plugged a 2GB flash drive (about $29 if you shop around) into a USB port, opening a dialogue box offering the option of using the unit for virtual RAM. The results were a noticeably faster experience.

Not everyone is as impressed. Bruce Perens, a Berkeley, Calif., Linux developer, argues that Vista's security-conscious intrusiveness alone is reason enough for users - especially those into video, music and program Internet file sharing - to think twice about staying with a Microsoft OS.

"Unlike Microsoft's previous operating systems, the main thrust of Vista is not to provide more functionality for customers, but to . . . impose pervasive digital-rights management," he said.

Along with its support for high-definition video content, Vista has launched HDCP, or High-Definition Copy Protection. The technology encrypts the digital signal from its source, foiling capture and copying.

"It is enforced throughout the system. You are the person not to be trusted," Perens complains. "It's a digital ball and chain to make sure you don't do anything the people who make music and movies don't like."

EWeek OS analyst Jason Brooks contends that with Microsoft controlling 90 percent or more of the market, Windows users probably will migrate to Vista now, or later, as software developers parade a slew of new programs and games for the system.

"If I ran Windows I'd probably upgrade [because] I like running the latest and greatest stuff," he says, though he adds XP users need not be in a hurry to switch - to either Vista or Linux. He prefers Linux for his home system.

"There's certainly a learning curve [but] Linux can be a very good option," Brooks says. "If you are quite used to Windows, moving to Vista or sticking with XP will be more comfy."

My conclusion? My heart may yearn for the open-source, or free software ideal of Linux, and the artist in me still gushes over Apple's elegant OS - but practicality must rule. Vista will inherit the super-majority of PC users Microsoft has built, and its own impressive and slick innovations make Vista a good choice.

bmims@sltrib.com