As you've read before in ComputerUser, Mac OS9 is a solid update of Apple's venerable operating system-and the last major overhaul of it before Apple releases its new-from-the-ground-up, next--generation Mac OSX, due this summer. This month's Mac Advisor offers some tips on getting the most out of Mac OS9.

First of all, don't even think about installing the OS if you're running anything less than a Power Mac packing 32MB of physical RAM with virtual memory turned on-or running the RAM Doubler utility from Connectix. Your Mac will run smoother and faster if you have at least 64MB of real RAM.

There are some potential problems with Mac OS9 you may have to overcome. Some users have installed it and run into problems with DVD movies. What's up? On Power Mac G4 and iMac computers that shipped with Apple DVD 2.0 Beta 2, performing a clean installation of Mac OS9 can result in the Apple DVD Player not working.

You'll know if this is happening to you when you're greeted with this cheerful message: "The application 'Apple DVD Player' could not be opened because 'DVDRuntimeLib/' could not be found." You can usually take care of the problem by dragging the DVD components (DVD Navigation Manager, DVD Region Manager, and DVDRunTimeLib) in the previous Extensions folder over to the new Extensions folder and restarting.

By the way, in Mac OS9, the Apple DVD Player is no longer listed in the Apple menu, but is found in the Applications folder. However, if you like having the DVD Player in the Apple menu, just make an alias of it and place it inside the Apple Menu Items folder, which is inside the System Folder.

Alas, it's possible that you'll still be having some problems with Mac OS9 and DVD playback. Apparently, the Audio Update for Mac OS9 (the latest version is 1.3, as I write this) resolves most of these issues. Apple claims the Mac OS9 Audio Update enhances playback for DVD movies and provides improved USB audio support and support for the Harman-Kardon iSub speaker that's in the new line of iMac DVs.

As it turns out, the iMac DV (digital video) systems aren't that great at playing DVDs because the video and sound drift apart. Apparently, Apple has switched the means of outputting audio from CD (and DVD) players to a purely digital format.

Although the problems aren't consistent from iMac to iMac, in many cases an inserted DVD pops and the audio gets out of synch. Again, if you're having problems in this area, go to Apple's Web site and track down the latest Audio Update.

Hopefully, these steps will have you up and running smoothly. However, there are a variety of inherent features in Mac OS9 that can speed up your day-to-day computer use. One way to do this is by using contextual menus, which contain commands that apply to just about any desktop item the pointer is on, including folders, document windows, and the desktop itself.

To open a contextual menu, point to an item and click while holding down the Control key. If more than one item is selected, the menu contains commands that apply to every item selected. If nothing is selected, the menu displays commands that apply to the desktop or window. To close the menu without choosing a command, just click outside the menu. (If you're having trouble getting contextual menus to appear, look under the Finder's Preferences window in the Edit menu and make sure the Simple Finder isn't enabled).

One of my favorite features of Mac OS9 is the Favorites submenu in the Apple menu, which offers easy access to the programs, documents, zones, servers, volumes, and Internet locations you use the most.

To add an item to the Favorites submenu, select the item in the Finder, then open the File menu and choose Add to Favorites. Or hold down the Control key and click the item in the Finder. Then, choose Add to Favorites from the contextual menu that appears. Or you can just drag items directly into the Favorites folder inside the System Folder.

There are lots of online resources for optimizing Mac OS9 and keeping abreast of any potential problems with the system. MacFixit is the most comprehensive Web site for Mac-related problems and solutions.

Version Tracker's OS9 Updates has the latest software updates for Mac OS9 and third-party tools. And Apple's Tech Info Library (til.info.apple.com/techinfo.nsf) contains lots of good data and answers to frequently asked questions.

Contributing editor Dennis Sellers also writes for several Macintosh-specific publications.