At least in the US & Canada where you can only buy HDTVs for the last several years, you probably don't want to create DVD slideshows -- the image resolution is decades old [roughly 640 x 480 on a PC's screen], the same or lower than the 1st common, cheap digital cameras. Worse, the DVD spec calls for interlaced video, & if a DVD rather than Blu-Ray player is used, so no HDMI, signal loss cuts the resolution further. It's all right for video where each field [1/2 an interlaced frame] is only on-screen for 1/60 second, but for static images, frankly the screen on your cell phone likely does as good, often better. Now that's not intended to insult anyone who likes to watch slideshows on video DVDs -- just saying that if you're going to go to the bother, rather than using whatever player to display a folder full of images [usually pretty easy with or without transitions], you might as well use a format that preserves more of the original quality. The electronics in a Blu-Ray or up-scaling DVD player may make your pictures look pretty good, but imagine how much better they'd look if you didn't throw away most of that original quality. You can use Blu-Ray on DVD [which probably would cost you next to nothing], use a TV or player with network capability [you can get Blu-Ray players with networking starting at ~$30], use one of the many hardware media players [they start at < $20], you might be able to connect the cell or tablet you have already & use that for a media player and so on...
The *only* advantage video DVD's have is that they'll work in every DVD player. 10 years ago that was a big deal -- today there are more ways to share your pictures than I could hope to count. You like the fancy transitions from one image to the next? Cool -- do your video & put it on Youtube... just stay [far] away from the DVD video spec.
If/when you do create a video DVD slideshow, here's what happens so you at least know what to watch out for...
The 1st problem putting still images on a video DVD is aspect ratio distortion. Pro's shooting pics of actors & such muddle through, but if you're putting pictures of friends & relatives on a DVD, consider their reaction if you make them look noticeably fatter or thinner -- most don't like to be made to look short & fat, while thin people can think you made them look gaunt if you go the other way. DVD video does not use square pixels like your camera & digital images do -- a couple decades ago when analog still ruled, they figured out that you could capture more data if you digitized a roughly 640 x 480 analog video frame to a larger 720 x 480 frame on your PC. Note that I say "roughly 640 x 480" because the analog broadcast signal is actually a bit oversized, though on a TV you'd never see that overage. That plus the math to convert square pixel video to DVD-type non-square pixels, & back again to display on TV, led to several frame size specs like 704 x 480, which is non-square pixel but cropped. If you're starting to feel a bit confused, you're not alone -- the people writing video software have never agreed on the best way to convert still images to DVD-spec video, so some say use 640 x 480 images, others say 655 x 480 works best with their apps, & some have yet other sizes they prefer. And if you like 16:9 widescreen, you might be surprised to learn that there is no standard 16:9 DVD frame size, nor is there a standard method or way for HDTVs to upscale DVD video [4:3 or 16:9] to fill an HDTV's wide screen.
Long story short, the best way to get results that match your original images is to research the software you're going to use, or perform some tests using test pattern images etc., then IMHO error purposely on the thin side, but just a little, to allow for those HDTVs that will stretch the picture wider -- in that case people might still look a bit thick, but with a little luck, no one will refuse to speak to you after they've watched it.
A 2nd problem is interlacing. DVDs are designed for analog TVs which use interlacing -- there's no easy & complete way around that since whatever plays the DVD is going to expect it, & will send the display a signal based on the video being interlaced, regardless whether that display's a CRT [analog TV], a LCD panel etc. An interlaced video frame is made up of 2 fields shown consecutively, one made up of all the even numbered horizontal lines, one showing all the lines that are odd numbered. When there's movement it's not bad -- the 2nd field shows a later picture of whatever's been recorded & the overall effect is smoother, so it's still used with HDTV [e.g. 1080i] when you're limiting bandwidth. Static images have no movement, so horizontal lines &/or sharp edges flicker. To reduce that effect software [editing apps, encoding apps, players, hardware drivers etc.], plus hardware like players & HDTVs can attempt to deinterlace video by blending or interpolating those pairs of fields into one frame -- that makes the picture blurred, so you can't win. If you use pans & zooms to add interest, splitting a static image into odd/even fields at 29.976 fps [NTSC DVD spec] is also where some [lots of] software has problems so you get stuttering.
A 3rd problem is color... DVDs are designed for analog players & TVs, DVD players are designed for analog TVs, and analog TVs are themselves designed for analog broadcast signals -- those analog signals are the weak point, not including pure white or black, nor several shades approaching either. The pictures you took with your camera or cell may have their range of colors compressed anywhere along the line, from the software you use to create the DVD video to the player to the [HD]TV -- using one or more apps can even cause the color range to contract, expand, contract again & so on, & the quality of expanding or contracting the color range varies depending on the app. As it is colors vary from one format or standard to another, and many [HD]TVs can't display the full color range either. Since this sort of thing is rarely advertised [e.g. you likely have no idea how whatever app alters the colors], the best you can do is test as much as possible every step of the way, at least initially to determine what does what -- otherwise you risk all sorts of problems... Most common is dark portions of the image turning muddy, but the overall image can change as well when for example software tries to avoid colors that aren't analog "TV Safe" -- certain colors, especially if/when over-saturated, make analog TVs go nuts, to the point that you can sometimes even hear the effects!
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Video DVDs had/have their good points, but at best sharing photos was never one of them -- it worked when there was nothing else. Frankly slideshows themselves are not universally loved -- those receiving them may say all the right, polite stuff, but privately they're often less than thrilled... at the least grandma & grandpa can't take their favorite pics of the grandkids out of the slideshow to look at whenever they want, or print them or share.
