I say this not to denigrate that browser, but instead to spare you any frustration you might otherwise feel. This site exists to explore the cutting edge of HTML+CSS design, and Navigator 4.x is, at four years and counting, just too old to keep up with most things that will be done here.
Designing Without Tables: Using CSS | Review || Books @ HTML Source. Using Cascading StyleSheet properties to define the layout of your webpages by positioning elements precisely and being able to set the margins, padding and colours of all elements independently is the current vogue in web design.
Stripping your designs of tables and writing lean HTML code offers many benefits — not least faster load-times and greater accessibility. Designing Without Tables: Using CSS takes you through the creative process of thinking in divs and layers, instead of rows and columns.