You should understand that all AVI files are not the same. Its just a file type that stands for Audio Video Interleave. Some AVIs are actually mpeg!
FRAPs is a particularly unusual beast in that in order to capture the screen in real time and not interfere with gameplay it uses even less compression that the standard DV-AVI file type that Pinnacle uses.
You might notice that the files are even larger the DV-AVI for the same duration.
Pinnacle can choke on these large files, or not recognise the codec depending on which version of Studio you have and what settings you used in FRAPs. Some of the lower resolution and frame rate settings can play in Studio, I believe.
This is from the FRAPs FAQ
Why is the AVI movie generated by Fraps so big? How can I reduce the size?
The filesize is big because there isn’t enough time to encode the
movie while the game is running. The movie frames are slightly
compressed, but still require a large amount of disk space due to the
high resolutions. Once you have finished capturing you should convert
the saved AVI into one of the popular compressed movie formats such as
mpeg or divx. Recommended programs for doing this are tmpgenc (Tsunami
Mpeg Encoder), and VirtualDub.
Using VirtualDub is quite easy. To create a compressed version of the AVI follow these steps:
- Start VirtualDub
- Select File->Open and choose the AVI in the Fraps directory you wish to compress.
- Select Video->Compression and choose the codec you wish to compress with (usually divx)
- Select File->Save As AVI and specify a filename for the new AVI.
If you have Windows XP you can also use Windows Movie Maker to
compress the video files. If you use Windows Movie Maker it's
recommended that you keep your Fraps video files at 800x600 or under.
Note the limits on using WMM. I'd guess you should apply the same to Studio, or use virtualdub to get the fraps files into a managable form.