OG it's worth taking off the old leaves - even on "babies" - they will already be developing the shoots for next year's leaves below the ground which will be at least twice the size of this year's. As Verdun says, they are susceptible to black spot and cutting off the old leaves will give them a better chance of avoiding infection. I usually scalp them in December, give them a mulch of compost, and the flowers and new leaves come up from January. Maybe mark their location somehow to make sure you don't tread on them in the meantime! I've used upturned hanging basket frames for this - works well and stops the flipping squirrel/ cats/ foxes disturbing them as well.
Red Dahlia - they are certainly expensive bought as fully mature plants but if you already have two, they will produce offspring and you'll eventually get lots of new plants for free. I leave the seed heads on once the flowers have gone over. The following Feb/Mar lots of seedlings emerge near the parent plants. You can give them a helping hand with a paintbrush (Carol Klein did this on GW) to ensure you get seeds. No guarantee what colours they will be of course, but that's part of the fun! I have sown some seeds in pots as well, but they seem to do much better if left to do their own thing - I just pot up the seedlings, grow them on a bit and plant them out as soon as they have true leaves. They don't much like being moved, so I prefer to get them in the ground early (plus it's easier to find the space in the border for a small plant!)
All in all, what with waiting a year for seeds to germinate, it is at least three years before you start to get flowers from seed. That's why they are so expensive. Once established though, they last for years and years. Verdun's recommended the best suppliers if you really can't wait!
Give your hellebores a good mulch with good organic matter now-ish, with perhaps some slow-release fertilizer as well to give them a boost, and you should be rewarded with plenty of flowers in spring.
Warning: they are addictive