Sounds like you have two problems.
One, getting that virus cleaned, and two, FP.
I don't known if FP is still the same but it always used to add it's own extensions that made pages not work correctly on different browsers. It may have been fixed since then, but it always left a bad taste in my mouth.
I prefer
eMacs, bbedit or
Vim, but they are more text based as opposed to WYSIWYG. Other than that it's
Dreamweaver or
KompoZer
IMO there are
many better choices than FP for editing.