for documents, OpenOffice is very nice it will read almost anything. Kinda like MSOffice on speed
for Realplayer, download RealPlayer for linux. Real networks ofers Realplay 10 for free download on their site
for windows media, there are a few options..... search google.com/linux for windows media player you'll probably find a good amount of results. I have heard good about XMMS and Totem, but I do more audio than video, so I suggest reading some user reviews of the applications.
Also, with windows media files, there are usually codecs required to play the files so whichever you choose, make shure to get the codecs also.