After looking at the previous response I don't know that the dreamWeaver page
gave you the best possible answer to immediately solving your problem.
The answer your looking for lies in "Tables".
Most web sites that maintain a fixed size regardless of the width of the
browser or monitor they are viewed on achieve that result by using tables to
control their page layout.
To see what I mean try this:
Open a new web page in the FrontPage editor.
Before typing any text insert a table. (You do this with the top menu bar)
table > insert > table
You will now be looking at the insert table dialog box.
In order to solve your problem easily and give you some experience to build
on, make only a few changes in this dialog box before hitting me "OK" button.
OIn the "size" area change the "rows" number from "2" to "1".
Then do the same thing to the columns number. (Change the 2 to a 1)
Then in the layout area where it shows you that the table width is going to
be 100%, make the following change.
Change the number "100" to "600" and select the radio button "in pixels".
(This should deselect the radio button that says "in percent")
Then hit the "OK" button.
You will now be looking at your page with a long narrow box extending 600
pixels in width.
Place your cursor in that box, and hit return and few times, and do some
typing or build your page inside that box.
Then save your page and preview it in a browser.
You'll notice that the box will keep all of your page content within its
borders acting somewhat like a rubber band that "wants" to be 600 pixels wide.
When you preview your page in a browser - any browser - you will see that
your contents are not allowed to extend beyond 600 pixels in width.
(There are a few exceptions to this, like putting an image that's wider than
600 pixels in this box will cause it to stretch the "rubber band" to fit the
picture.)
This is just the beginning of true page layout techniques.
Back in the FrontPage editor, if you right-click inside your "table" and
select "properties" you'll find that you can do a great number of things with
tables.
The first thing you might want to do is to turn off the ugly gray line that
defines your table in the browser. You can do this by changing the width of
the table border from 1 to 0.
Page layout is normally accomplished using sophisticated table and "cell"
combinations.
The main advantage of this is being able to keep pictures and text in the
same relation to one another regardless of the screen size or browser that
they are displayed on.
Be aware that you can Place tables inside tables, divide tables into
"Cells", and specify the colors that you would like for borders and
backgrounds.
Good luck and have fun, creative use of tables has been referred to as "the
keys to the kingdom" in Web design.