Q: extracting small clip from a .avi file

Greetings!

I'd like to extract two sections less than 1:00 minute long apiece from
a .avi film I downloaded from the internet to use as an example in a
lecture without having to mess about with finding the right spots. (I'll
do that if I absolutely have to.) I do not know what codec the file
uses, and I have no idea how to find out. It plays in VLC 0.8.4 but not
in QuickTime. I have no expertise in working with video files. I have a
G5 DP 2.0 which has iMove 5.0.2 and QT Pro 7.0.4. I could download
shareware for this purpose, but I'm not going to purchase expensive
software like Final Cut Pro or the like just for this sort of thing. I
do not have access to a PC for this purpose, although I do have VPC
running XP Pro, slower than you can possibly imagine.

My question is, can I do this in a reasonable time, with no enormous
learning curve and no deft touch with video-editing software? Pointers
to information on doing what I want would be greatly appreciated.

TIA!

George
.