add subtitle to mpg/wmv file

I need to? add subtitle to mpg/wmv file, very minimal work to be done, just to add +/- 10 subtitles in total to 4 video files.? I did create .srt file and they work on my computer and I can see the subtitles but I can't seem to make it work on another computer, some of the clipos are scrambled...and the subtitles are not working. i need to keep the file in their original format? mpg/wmv to inlcude them in a powerpoint presentation.? maybe if we could add the text directly in the video insted of subtitle that could work...I'll let you decide I"m not good with videos. ## Deliverables i need this done for September 6th,2009. Once the projetc is accepted I"ll share with you the user/pass + adress to download the videos