Microsoft Corp.’s next installment of Windows doesn’t launch until October, but deep discounts on some versions are available through Saturday if you want to pre-order. Before pouncing on this deal, make sure it’s right for your PC.

There are plenty of reasons why you’d want Windows 7. It appears to be more stable — less prone to crashes — than previous versions of Windows. It’s less annoying than Vista, which could deluge users with security warnings and other nagging reminders. Windows 7 has a cleaner, simpler interface.

One thing that isn’t simple about Windows 7 is the flavors it comes in. Microsoft said it tried to keep the options easy, but that didn’t happen. You still must choose from Home Premium, Professional or Ultimate versions. (There also are Starter and Enterprise, but neither are sold directly to consumers.)

The consumer versions come in two variations, an upgrade and a full version. If you already have a Windows computer, buy the upgrade. If you’re building a computer from scratch in the basement and don’t have an unused copy of XP or Vista that you’ve already bought, you’ll need the full version.

Retailers such as Amazon.com Inc. and Best Buy Co. are taking pre-orders for the Home Premium upgrade and the Professional upgrade, for $50 and $100, respectively. In the fall, those will cost $120 and $200.

Here is advice on how to consider a Windows 7 upgrade, depending on various scenarios:

- If you have Windows Vista Home Premium or Business, and you want the equivalent Windows 7 edition, pre-ordering the upgrade makes sense. You can trade up from Home Premium, or down from Business, with no extra hassle during installation. When your disk or download arrives Oct. 22, your PC will get a makeover, but your files, programs and settings should remain intact. (Don’t tempt fate….

Read more here:
Windows 7 Is On Sale. Should You Buy It Now?