Your right laptop's "generally" aren't the best computers for video editing.
I am not sure where you read to burn your movie directly to CD when having
issues saving it to your hard drive but that is not good advice as you are
finding out. All you end up doing in that case is creating a coaster out of
your CD. There are a lot of possible reasons for not being able to save your
project to your hard drive but we'll talk about some of the most common.
1) One is simple. Find out if your hard drive is formatted FAT32 or NTFS by
right clicking the drive in "My Computer" and selecting properties. If it is
formatted FAT32 then you are limited to a 4GB filesize which is pretty
useless in video editing. If it is NTFS then your ok so we can move on.
2) You said you "think" the clips from your camera are AVI. Did you capture
them from the camera using WMM or transfer them a different way? You want to
make sure the clips are AVI and not MPEG. If they are MPEG they should be
converted to AVI. If not then we can move on but first, do you have audio in
the project and is it MP3? If so that could also be the problem - convert it
to WMA or WAV.
3) I know you said your project is only about 20 minutes long but they may
be too long for your laptop's resources to be able to render properly if you
have a lot of transitions, overlay's, effects etc... making the project too
complex. If this is the case see my website Movie Maker Trouble Shooting and
find the "How to Split a Project" instruction and split the project into
pieces. If you don't feel complexity is the issue here's one more.
4) Honestly I just like to hear myself type..
Your best bet is probably
to transfer the clips to your desktop computer and do the job there.
-Wojo