First of all - most apps can be configured to export pretty good HTML - even MS apps do it pretty straight and are *much* at it than expected.

Then: really learn to code HTML, so you are able to recognize good or bad code.

Finally: most of the webservers use Apache, sporting mod-gzip. This on-the-fly compression reduces the size HTML-page transmitted to a minimum - it doesn't matter if you have a nicely structured code (you should *always* try to do it that way, makes debugging a lot easier) or not - the difference in size is only a couple of bytes. (sidenote: an extra table or two don't matter either)

Rather learn to do your graphics right - with mod-gzip, your HTML is rarely more than 2k, usual graphics size is about a hundred (!) times as large. Obviously, this is the place to save bandwidth and loading time..