DVD standard uses
a) Mpeg 1 with specific resolution
b) Mpeg 2 with specific resolution
Quicktime, WMV & miscellaneous fit neither of these 2, and will need to be converted to Mpeg1/2 to be written as a standard playable DVD.
If it's just a matter of sending to people/storing for use on a PC, just burn them as data files without converting them using recode
You can also try VOB's DivxtoDVD, which will likely convert them. (it does more than just avi's).