You could separate your table into two separate tables (the first column as the first table, and the rest as the second). Then, you can either place the first table in a div with position set to fixed at left:0 and top:0, or just set the second div (which contains your second table) to have overflow:auto.
Also, remember to move the second div to the right, otherwise they will be on top of each other!
Hope that helps!