If you want to share a video with friends and family members, but not have to worry about file formats and codecs (NTFS, FAT32, etc.) that may be incompatible with their computer/device, upload to Youtube. You don't even have to make Youtube videos public, as there are a couple of options that keep your upload out of public searchability. "Private" allows ONLY the person logged into the account to view the video, most likely you (the uploader). However, "Unlisted" allows the uploader to send a simple link out to acquaintances, who can then watch it on their screens without being logged in.
When you plug a drive that's been formatted for Mac into a Windows PC, you may find that it isn't readable. This is because Mac uses the HFS+ format natively, whereas Windows uses ExFAT or NTFS. One simple way to make the drive readable on both platforms is to format it to ExFAT, which both operating systems can understand. This will erase all contents on the disk, however, so you'll need to transfer those files to a safe place first.
If you can't reformat the drive, there are programs available that will make it possible to read a HFS+ drive on a PC:
If you have old files saved in obscure formats, it can be difficult to find a program that will open or convert it. Even if you do manage to find a program that could recognize your files, it could very well cost you. Fortunately there's a free site that can point you in the right direction: OpenWith.org.