Although I do not use ulead I would think it is simple to do.
If you find the button to create DVD it should produce the DVD folders (vidoe_TS and audio_TS) on to your hard drive. You should be able to make it do this by selecting 'create folders' rather than 'burn disc'.
You can then burn to a disc whenever you want using Ulead or, my preferance, Nero. In nero selct New, DVD, DVD Video, Make sure the left payne is in the video_TS folder then find you newly created dvd on your hard drive in the right payne. goto the video_TS folder and drag all the files (.VOB, .IFO etc) to the left payne and then burn the disc.
Burning at a slow speed (4x or 8x) will often get better results.
Another way would be to use something like WIN AVI, that will take your joined up video file (mpeg, avi etc) and produce a disc, simple but effective.
If it is in MP4 format, you should be able to find an assortment of apps that will convert the file to DVD. May take a little bit of internet searching but should be worth the effort.
Also have a look at afterdawn.com/