Override is a common name for accelerating the response time of a LCD panel. The 226BW is by default a 5ms response panel but measures 2ms when the override feature is enabled.
FOV or Field of View is the angular extent of the observable world that is seen at any given moment. In laymen's terms it means your scope of view left to right. With 4:3 you don't see as far left to right.
The more you browse this forum the more you'll see the term FOV used in asking if a game supports widescreen well. Those that don't crop the image in such a way that you don't get more view left to right than you would on a 4:3 display.
Here's an example using a 4:3 crop on that 16:9 screenshot I linked to earlier of WALL-E.
What you are essentially getting with proper widescreen support is a little more view left to right than the area within the crop lines would show in a typical 4:3 display. To achieve this the FOV has to be different for WS than it is for 4:3. Basically it means a wider angle of view is shown by moving the point of perception (game's camera position) farther away. If you were to put the screenshots I showed above side by side and look at one right after the other you would easily see that the 4:3 one has a closer view and the WS one has a slightly more distant view. In other words on a 4:3 display you'd see the area within the crop lines in the pic above, but at a slightly closer view and a HUD adjusted for 4:3.
On viewing distance, much of it is personal preference, which is why I usually stress a "comfortable" distance. Two feet is about the norm for a typical 30" depth desk that has no KB pullout tray and a CRT display. I have a 30" depth desk with a KB pullout tray so I sit with my eyes about 3' away from my 21" CRT screen (20" viewable). Keep in mind though if you're using a CRT now you'll have more room to set the thinner LCD panel farther away. It depends on the game though too. If I'm playing a game where I'm making distant shots I often sit closer. Conversely if I'm playing a game like Area 51 that has a very close FOV, I sit farther away or it will bother my eyes.
If you combine all of the above facts that a 22" 16:9 roughly equals a 19" 4:3, that 16:9 games that support widescreen well (and most do) have farther views (FOVs) and that you can put a panel display farther back on your desk than a CRT, the worry about size becomes a non issue. These are the reasons I think many when going from a 4:3 CRT to a widescreen panel often make the mistake of not going big enough, rather than going too big.