Copying movie clips between computers

I am not that familiar with iMovie version 8 but I think the file structure is the same as version 9. So i would suggest you go into your movies folder on Mac Book Pro where you found the iMovie Events folder. You should also see an iMovie projects folder. Copy these two folders to the Movies folder on your iMac via your usb stick which you may need to format as MacOS extended journaled. Most usb sticks are formatted Fat 32 which has a file size limit which might be a problem. If the files copy ok then you won't need to reformat. After you have the two folders in your iMac's Movie folder open iMovie 10.1.8 and in the file menu select update projects and events. iMovie will convert your projects and events to be compatible with 10.1.8. I know this works for iMovie version 9 so I hope it works for your iMovie version 8.

Yes you can select the events in the events folder that you want. Just create a new events folder( name it the same as the original) and copy the events into it that you want. Same for projects. iMovie will see both folders and you can choose which to update when you select update projects and events. If there is a problem change the name of the original iMovie Events folder so iMovie will only see your new folder with the events you have selected. Not sure I understand your second question. The video clips in the AVCHD format are .mts files. Try moving the AVCHD folder to your desktop and Contro-clicking on it and selecting Show Package Contents. Find the BDMV file and do the same. You will see a STREAMING folder. Open that and all of your MTS movies will be in there. The mts files should open in Quicktime player and you can save them as .mov or mp4.