peewhy,
If I'm understanding your problem correctly, one solution could be to use the Featured Products module instead and rename it to "New Products for March". This way, you can handpick exactly which products would appear. The downside being that you would have to manually update the month every four weeks. I'm sure you could add a little code to show the current month. Or just call it "New Products".
Of course, if you want control of the text that appears as well, I would instead recommend adding a html table to your main page using the Define Pages Editor and designing it to match your site.