Yes, it is. In Word, you can change the font size to whatever you want (including decimals) by clicking on the drop-down font size list and 'typing in' the size you want rather than selecting one from the drop down list. You can also go to the Font dialog and type in the size you want rather than selecting one from the list.

To change the line spacing, go to the Paragraph dialog box from Tools (Word 2003), and change line spacing to 'exactly', then the number of points, or 'multiple' and something like '1.25'.

Cheers,
Andrew