I had 2 questions on Yom Tov.
1) If one at meatloaf or challa on the first night and wanted to freeze the leftovers to keep it fresh for the future is that permitted? In this case there is a sefek if the leftovers will be eaten soon in the future. If one usually freezes solid foods for freshness is that still a problem of hachanah?
2) If going into to yom tov one lit the yom tov candles(that last for a couple of hours) and then realized that the candle that lasts for days was never lit. Can one lite that longlasting candle from the yom tov lights, even though the point of lighting the long lasting candle is just to have a flame over yomtov to use in general but no specific use (if the yom tov candles go out without transferring the flame onto the long lasting candles the rest of yom tov will be without a flame)?
1) It is permitted to return the meatloaf/challah to the freezer, and this does not involve a prohibition of hachanah.
There are two basic reasons for this. One is that there is no obligation, of course, to leave food out on the table, and it is permitted to tidy the house by putting the food away. Once it is permitted to put the food away, there is no obligation to place the food in the fridge, and it is equally permitted to place it in the freezer. This is not an overy action of preparation for weekday, and therefore it is permitted.
An added reason for leniency is suggested by Rabbi Peach Eliyahu Falk (in Machazeh Eliyahu; I don’t have the sefer before me now to write the marei makom), who explains that the prohibition of hachanah does not apply to actions of preservation. If a person wants to prevent the meatloaf from going bad over time by placing it in the freezer, this action is not defined as preparation by as preservation, and therefore no prohibition applies.
In the particular case of the question, there is added reason for leniency, because it is possible that one will wish to eat the meatloaf during Yom Tov, and freezing if for the purpose of Yom Tov/Shabbos. However, there is no need for this added rationale.
2) There is no problem of lighting the long-lasting candle from the Yom Tov lights. It is permitted to derive benefit from the candles, and because there is a likelihood, and at least a possibility, that one will need a light (a flame) over Yom Tov (e.g. to light the Shabbos candles on Friday), it is permitted to transfer the flame.
Best wishes and gemar chasimah tovah!