The process of editing and rendering is NON-DESTRUCTIVE to your original footage. If you have any concerns for your original footage, by all means back it up onto another hard drive, DVD, flash drive etc.
I am working off my Vegas Pro V10 copy here at work. If you have a different version it might be SLIGHTLY different, but the basic process is the same.
If you are going to output to a DVD then you need to render two files:
In Vegas, select File>Render As...
1) Video portion of project as a MainConcept MPEG-2 file, using the DVD Architect NTSC Widescreen Video Stream template.
2) Audio portion of project as a Dolby Digital AC-3 Pro (*ac3) and using the Default Template.
Note what directory/folder you rendered these two files two, because you will need to reference them next.
After you have rendered both files (audio & video), Open Sony DVD Architect, then select File>New...
If you are only going to have the one movie on the DVD, then select Single Movie. I recommend that you start here, before you wade into creating a multi segment project with a DVD menu structure (Menu Based). The Disc Format should be DVD, the Project Video Format should be MPEG-2 720x480-60i 16:9 (NTSC) for a widescreen DVD output, otherwise use MPEG-2 720x480-60i 4:3 (NTSC). When you have made the appropriate settings, press the OK button. You should have a blank DVD in your DVD Writer at this time. When the Open Media dialog box comes up, enter the name of the VIDEO file you rendered in Vegas Pro, making sure the Open: Audio and video streams option is selected at the bottom of this dialog box (so both the video and the audio portion of your project will be loaded).
Select File>Make DVD... then press the Prepare button on the dialog box that appears. When the Select Prepare Folder dialog comes up, accept the default file location already displayed and press the Next > button. When the Review Message List dialog comes up, select Next > again. When the Check the Subtitles and Menu Highlight Masks dialog comes up, select Finish.
DVD Architect will do what it needs to prepare the audio and video streams for the DVD, then this dialog will appear.
DVD Architect will have processed your audio and video files and prepared them to be burned to the DVD - you're not quite done yet. Press the OK button to dismiss the dialog, the select File>Make DVD... again, this time selecting the Burn button, then when the Select Prepare Folder dialog appears, accept the defaulted file selected, then select the Next >button at the bottom of the dialog.
When the Review Message List dialog appears, select Next >. When the Check the Subtitles and Menu Highlight Masks dialog comes up, select Next > button.
Then the Select Burn Parameters dialog comes up, enter a name for the DVD in the Volume Name field, make sure the default DVD burner device selected by DVD Architect is OK, and the Burn speed is compatible with the blank DVD you are going to burn your project onto, then press the Next > button.
After your DVD is completed, it will eject, then ask if you want to burn another one. That's the basic process in a (very large) nutshell.
There are lots of additional things you can do to improve the project, but this will get your feet wet in how to create a DVD from start to finish.
If you followed along with the above and still have questions, post and someone will help you out.