I am not very if this has been asked before (probably yes), may I ask which software could help ripping part of a movie into a avi or whatever format? Say converting the first 5 minutes into one file and 43-47th minutes into another?

Freeware prefered. Thank you.

 

Don't know about freeware, but Pocket DVD Studio should do it.

 

VirtualDub works fine for me.
You might need the codecs you'll encode to, though.
AutoGordianKnot works excellent, and if you want to use VirtualDub and are in need of codecs, you can simply install both(AutoGK includes a bunch of codecs) and you should be fine.

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2. Have fun.