There doesn't seem to be much variation between DVD-Rs, but if you're looking for a reliable brand that is still decently priced, Memorex might be what you're looking for.
The DVD-R is the normal size for a single layer DVD, 4.7GB. The recording speed is fine, I usually keep mine on 4x just to make sure there's minimal skipping and errors. At 4x burning speed, it takes around 15 minutes to burn 4.28GB of data onto it, which will vary depending on several things such as the software you use.
The case that they come in is alright, but I don't like it as much as some other brands which have a better locking system. This isn't that big of a deal, just be sure that the tabs are lined up before trying to pick the whole tower up.
The only real complaint I have about them is the design. The front is cjeckered with boxes except for a small box on the top and bottom. This is fine for anything with short titles, but if you're trying to fit something with over 5 words on it you'll have to write pretty small or write outside of the box to fit it all.
Overall, this is a solid brand of DVDs that will give you error-free results time after time, with only minor design flaws.