First to the Acrobat problem...version 5 is the correct one these days. Hope I spotted only a typo, Acrobat Reader can only read *.PDF files, not PFD files....
Try to search on your computer, there are more PDF files, can you open them? There maybe a problem with the site or even with the files you want to see on that site.
Your card reader....the software for it, is that for W98? Go to the manufacturers website and download the correct version....I am not convinced that W98 is included in your basic system requirements of the reader.
Almost forgot, since you are talking about W98 as your system software...what kind of USB port do you have? I am somehow certain that your system is pre 2000 and will have USB 1.0 port(s)...and your card reader may only be USB 2.0 compatible...which may be acchieved if you fit an expansion card to your PC with USB 2.0 ports on it, but that is another story.