Well..I have footage shot in HDV with a Canon XH-A1..Put it in the time to work with it..project is done. I rendered it out asa mpg with a calculated Bit Rate to 16:9 for a Standard DVD. The file size of the DVD is 4.22 or something like that. When I place it in DVDA it comes up at about 5.9. What would be causing this?

What would be causing this?

This has happened to me numerous times and it's because DVDA has a long history of incorrectly reporting file sizes.
You would think this is something that would be fixed by now but it hasn't happened yet :-(

If you know that the combined total of your MPEG-2 and AC-3 files is under the limit, ignore the warning and go ahead like you normally do.
Unless something else is wrong, DVDA will continue on it's way as if it never warned you in the first place.

Make sure you save the video and audio as seperate streams - this fixed that issue with DVDA for me.
Another thing, look at Perrone Ford's workflow in this thread: http://www.dvinfo.net/conf/what-happens-vegas/271329-maximizing-hd-sd-quality.html for a much improved downscaling from HD to SD as Vegas and DVDA do a pretty lame job of it.

Dennis, I've been rendering separate streams ever since I started using DVDA and it still does it to me periodically :-(

How do you mean to render as seperate streams? Literally render the video/audio seperate..how does it match up in the menu?

That's right Peter.
Video gets rendered as MPEG-2 (w/o audio) and audio gets rendered as AC-3.
Give both files the same name (i.w. myvideo.mpg and myvideo.ac3) and render both to the same folder.
That way, when you load the video file into DVDA, the audio file loads automatically.
Edward Troxel covers this process in Vol. 1 #7 of his newsletters (http://www.jetdv.com/vegas/forum/viewforum.php?f=5&sid=35b95ebb131ff4f6b5eeb490b1ce1cab).
They're an excellent (and free) resource.