Video processing

[Jonathan Hutchins]

I have some .ts video files that are just under 7 gb in size.  They're 1080p 
HD, and nothing I own appears to want to work with them.  VLC and mplayer 
both seem to freeze on the first frame, avidemux reports it's unable to 
determine the aspect ratio after trying to index the file, and tovid's idvid 
returns 

/usr/bin/idvid: line 261: 16#Stream: value too great for base (error token 
is "16#Stream")

This is on an Athalon 2500 running at 1.8 Ghz with 512 M of ram.  What I'm 
wondering is if I don't have enough ram to handle files this big, or if a 32b 
processor/OS just isn't capable of it, or if the files themselves are 
corrupt.  I have heard of people handling larger files with avidemux, so I 
know it's possible.  Suggestions?