graphs on the web

I recently asked for advice about the best format for posting a lot of graphs on a web site so they could be either read on line or downloaded and printed.  In case this information is more generally useful, I’m summarizing what I learned here. 

graphs on web: technical question

I want to post information that consists of ~200  graphs on my web site in a format that will be accessible to the most people.  I don’t want to spend a ton of time doing this and would prefer to have the files as small as possible.  I am generating the graphs in Stata, which can produce files in these formats: wmf, pdf, png, tif; I can also have software that can translate into these formats: jpg, gif, bmp.   The .wmf graphs I produced are mostly 8-10 kb each, but there is another set that are 70-100kb each.  What format do you suggest I put them into?  If you want to give feedback about legibility etc issues based on more detailed knowledge of what is in them, please let me know and we can communicate privately.