mp3s may give me higher density storage but I can't play them back as universally (I have to use the mp3 player in my computer or DVD player) and the menuing in my DVD player makes it difficult to branch through hundreds of recordings; your milage may vary.
I know that mp3s can sound good or bad. I also know that DVDs can look better than a laser disc but the source materials or poor or the compression is too weak, the image will be substandard. The potential for the technologies is not always reached.
I plan to work on getting a good sound sample from my vinyl because I will hear it in the repeated playback of those recordings. An extra hour in preparation will pay off in the continued playback over years.
With 45s, there are times they are great to have. There are also times where it is a pain to sit near the stereo so a new side can be placed every 2:30/4:00 minutes.
Aside from getting the best possible vinyl playback equipment and the best possible sound card to handle the A/D conversion, I recommend getting a copy of SoundForge and the noise reduction plugin. Academic versions are available for non-commercial use.
The noise reduction is very sophisticated. It has a click and pop remover that is infinitely configurable to prevent audible side-effects. If you don't trust the automatic mode you can mark each and every click and treat it individually.
There is also a very sophisticted noise reduction process that can sample a "silent" grove, build a noise profile, and remove the noise from the entire recording without introducing "breathing" effects. If a touch of crackle makes you feel better, you can apply these these processes lightly, getting rid of only the most annoying pops.