Forget tables, after all this is the accessibility forum, isn't it. Your choices are as follows:
1) Completely fixed size layout with auto margins
2) Semi-fixed/ semi-fluid layout (some fixed columns and some fluid ones)
3) Fully fluid layout. (No horizontal scroll bar when you shrink it)
Option 3 is ideal but option 1 & 2 often most practical. Option 4 is starting to look like a lot of work but one thing it does allow for is that images can be scaled based on screen size.