What specification is your PC? (Looking for CPU and RAM specs in particular here.)
Also, are you sure that you've got H.264 video? There are many other video formats out there that would cause the players to fail. Download GSpot, it lets you view information about the file.
Depending on the size, and barring any copyirght restrictions, perhaps you could upload it and I'll take a look. I have a metric ton of webspace which you could use as online storage if needed.
More information would also help, so if you could tell me what the file extension is (MKV, MP4, M2TS, EVO etc.), what the source of the video is, what the resolution of the video is etc. that'd be good.
Another utility that might be of use, if it is a TS, M2TS or EVO file is eac3to. Running the following command on such a file will reveal information about the tracks:
eac3to "C:\path\to\file.evo" -check
There are many other utilities that could help here, but this post would turn into a big list of links without me knowing more about the file.