Assuming you mean from video tape (VCC200, Bata, VHS, S-VHS, 8mm, Hi8) you need a deck to play back the tape, a head cleaner (particularly if playing 20-30 year old tapes) a video capture device and appropriate audio and video cable RCA phono (left, right audio perhaps to a 3.5mm mini jack and RCA video or S-connector.
There are some inexpensive video capture USB dongles. I use Hauppauge 3000 Freeview/Freesat TV card, which after several upgrades to the software does a good job of importing and better than several of the cheaper composite and S-video input cards I tried.
WinTV imports to .ts and I use VideoReDo to edit out unwanted material (head and tail the original recording) and output to a smaller .mpg file. Nero does the same with slightly better compression without lost of quality.
For a better job and more powerful software I use a Canopus ADVC300 external box. The supplied Neo software edits digital video (DV format) as native and conversion to mpg for DVD or HD tape to Blu-ray as well as importing analogue video formats to DV (edit, merge and add effects along with DVC inputs) and optionally output to a range of other formats.
DivX is available on many DVD/Blu-ray players, portable devices and computers. Most options result in JPEG like compressions. E.g. A clip of a kitten at Home theatre option doubled the number of whiskers seen. Using DivX Author at the highest quality made a far more acceptable job and a much smaller file than the original MPG, but several times larger than the standard options gave.
I have also experimented with converting AVI (native DV input format) to MPG. This should reduce the size of the file and in DVD format give an acceptable quality. This was not always the case and some effort had to go into the options to get it right. If the imported tape is not to be edited with A/B roll over titles added or dubbed then VideoReDo works perfectly for cutting out unwanted material and does not convert when saving but a frame to frame copy so so quality is lost in the edit.