LyX ⇒ PDF output looks like crap

[meho_r]

I'm actually not sure what Type 3 fonts are, I suppose that's part of the problem.

I'm seeing all the solutions are to enter code, so I gather if I'm to make any progress with this, particularly getting help from the community I'm better off learning to write the code? How does LaTeX compare to HTML in terms of difficulty/ease of use?

That depends on the problem at hand. In this case, you don't have to fiddle with code (except probably the line frabjous mentioned: \usepackage[T1]{fontenc}, although even it shouldn't be necessary since T1 fonts, if present, are used automatically). Also, you should be able to change fonts to sans directly from LyX, without entering code, by changing settings in Document > Settings > Fonts > Default Family > Sans Serif. If you still get bad fonts after that, then the problem is almost certainly in fonts: you probably haven't installed them so LaTeX is using T3 fonts.