Hot Dog to Dreamweaver

Hello,

I began playing with Web pages in the mid-nighties and it seemed at
the time that the only editor in town was Hot Dog from Sausage
Software. Dreamweaver emerged soon after but Hot Dog
was a robust enterprise with active forums, regular upgrades so I
stuck with them. Some idiot bought the Editor and Sausage Software
sometime around 2000 and the whole orginization just froze in time.

I still use Hot Dog Pro 7 and my pages still seem to work fine in
Firefox and IE, but I'm becoming more serious about my sites now and
and don't want the browsers to leave me behind.

Questions:

Has anyone had experience moving web site files/photos from Hot Dog to
Dreamweaver?

Is it important to use XHTML rather than HTML?

Is Dreamweaver worth $400.00? (i'm not questioning
it's value It's just a lot of money to spend replacing somethng
that is working.)

Thanks for your time,

Den