adobe flash player maybe the best selection for view .FLV .SWF flash files. or try to transcode this videos to mov or mp4 formats. there are many great video converter software can help to converter video among all formats including some freeware. such as Handbrake and Freemake. completely free and no other cost. Handbrake has both windows and Mac version. best solution for convert flv to mp4
for all users. have a try.