Hey! I have faced the same problem sometime before. Its either a corrupted file or one of those files with lost chain linkages. Try one of these methods to fix it.
1. First try VLC Player. If it plays the file fully its good. Or else...
2. Try Media Player Classic (man its an awesome player). It plays almost anything from mpg to mov through realmedia files. Remember. Its called "Media Player Classic" and it has nothing to do with MicroZoft. he he...
3. The last player which you must try is Kazaa's AVIPreviewer. It plays any AVI even the corrupted ones.
4. If you use any one of the above files and it plays fully and continuously, its fine and OK. But... after 51 mins, if you see jumping frames and discrete play, then you should realise that its time for a file repair.
5. Use VirtualDub if its an AVI file. Its an excellent tool for repairing etc. Save the file again. It should work well.
6. Or use one of those freeware/shareware AVI fixing programs.
7. If its not an AVI file, my suggestion is to dump it and search for a better file.
Thats all folks!
Vaasan
Hackers are not made... they are born.