Well, I proved that Microsoft Frontpage is bad by testing the old layout in Mozilla Firebird. The results: It didn't show correctly
You can't depend on Frontpage. Well, you can depend on dreamweaver because webpages from there are compatable with IE6 and Mozilla plus it has Automatic XHTML support. Dreamweaver costs about 399 US or higher (you gotta save your money) if you are too... lazy to code.
But the best, free way is to use HTML from scratch and then validate it after you finished.