Dvd5 holds approx 65 mins compressed to 8mbps (it really depends on menus, and audio source too)
8mbps is the highest most recommend for DVD as over that can cause issues on playback, I personally would never try to go under 6mbps
Dvd9 is dual layer and will hold double (not really double, and again depends on audio and stuff)
With that said if your video is 6.75 gb and you don't want to break it into multi disc you will need to use dvd9 and should have no trouble getting that on one disc since it will hold over 7gb
Now with dvd9 you need a layer break point. The layer break must be at a point where layer one is bigger in size/time compared to layer two.
(DVD) I have a Mac so I can't give exact direction but it will give you the basic idea...
Capture the VHS to your comp, which it sounds like you did, in .dv or .avi (uncompressed you will get a file size of approx 2gb per 10 minutes, so if you captured correctly your video is approx 33 minutes)
Edit anything you want to like fades, chapter markers, audio adjustments, whatever
Export to DVD (you should end up with files that are .vob among a few others)
These files should be in a folder named video_ts, you will also want to have a empty folder named audio_ts for better playback ompatability and it's not a bad idea to have a folder named extras_ts that you put the text file and md5 in
After ou have the files simply use whatever program you use to make md5 for audio to make one for the video_ts folder
Goto your torrent program and pretend its a audio upload, it's exactly the same from there
(YouTube/iPad) you don't want the DVD files for this
For this you want .mp4 or some other comparable file
Generally speaking you will just export to the quality settings you wish based on the file size you want in the end
Of course these files you can't torrent at ttd like the DVD files above