I use DVD flick but of late it doesnt seem to work that great... Sometimes they will play in the PS2 other times comes up with the red screen insert PS2 disc blah blah... Might have to try Nero like mentioned above
If someone sends you home movies, that you wish to burn to dvd you may want to go and buy a cheap dvd player $50/$60 that supports divx..... in the long run it will work out cheaper. ie 6 movies to a disc compared to 1 (assuming these are 2 hour home movies), + whatever your software costs, +10 mins to burn a data dvd compared to an hour to create a dvd movie disc. for a lightweight burning program for data, cdburnerxp is awesome.
If you want to burn the movies onto a DVD, you can use a program called "convertXtoDVD". This program will produce .vob files which can be burnt directly to a DVD. The end DVD quality will depend on the quality of the input file. Basically, the less compressed the file is, the better the quality the DVD will be.