In xl2003 menus:
Select the range (say A2:B10)
And use Format|Conditional formatting
Formula is: =$a$1="a"
and give it a nice format
If you wanted to format columns B:G based on the value in column A -- so each
row is based on the value of column A of that row, you could:
Select your range (say (B2:G99) and with B2 the activecell, use:
Format|Conditional formatting
Formula is: =$a2="a"
and give it a nice format
Excel is smart enough to adjust the formula nicely for each row in your
selection.
The $ in front of the A means to keep it fixed. No $ in front of the row means
to adjust the row number.