Layer Properties > Symboloby > Show:

JFBellemare

Make the "Show" box (Features, Categories, Quantities, Charts, Multiple Attributes) wider. 
It's not like the contents change - ESRI knows what the options are, why not make the box the proper size?

While we're making boxes the right size, why not resize the Symbol-Value-Label-Count one too?
Especially the Value column, it needs to be much wider.

RichardFairhurst

The whole dialog should be resizable.  I have layers with over 300 symbol categories (sign faces) and you can only see about 6 symbols at a time.  I should be able to resize the horizontal size when I have many codes grouped together and the vertical size of the dialog to be able to see as many values as my screen will fit when I need it.