I should think you could prune any of them while they're indoors. If they're hollow stalked I'd definitely wait until after the last frost to plant outdoors.
My 'hotlips' is surviving and still in leaf in its original pot outdoors where it gets afternoon sun. Probably grew roots out the pot holes to get moisture and nutrients from the soil under it.

Hey Shannon! Usually if something I'm rooting gets too leggy in the winter I just snip it and stick it in water too. Should work for most potted outdoor plants as well. So try rooting your prunings.

If you could hang a gro-light from the window frame, it might help with the light levels - have it on during the day. If that's not an option, nor putting a 100W lightbulb in the nearest lamp and leaving it on during the day - then I would think you could trim away. I might trim them back anyway, since you don't want lanky plants in the groundfor the summer. I've not tried it, but since tomato growers either keep a fan on their seedlings, or run over then with a cane wand or a hand, to simulate a breeze - it makes the stems stockier - maybe you can "rough-up" your overwintering plants once a day, as though they were in a stiffish breeze outside? That might help keeping them a bit shorter after trimming them.

Cheer up. Despite the present evidence of cold temperatures, spring is on its way - your plants can go outside in a few more weeks, maybe as many as 6, but the end is in sight!

I don't have a tall lamp handy but do you think that a desk lamp would work? I could put it on the table and shine it on it.
Rootdigger- I think I got the banana from you and it seems to be doing fine. I pulled the dead foliage off of it and now I have new little nubs poking through.
I did receive a pleasant surprise today. I was checking some of my plants and I "found" my red sheild hibiscus in a bucket and it seems to still be alive. It has been living in a sand bucket with no drainage holes, in the freezing cold weather and the stem is still green. So I repotted it in a pot with holes, cut it back, and it is now on my porch with protection. I had written it off because I didn't have room for it inside. I wintersowed it last year and I had more seed so I wasn't concerned so much for the loss but hey it wants to live I'm going to try and help it. Shannon

If the desk lamp is rated for 100W, it should do fine - some are rated only to 60W - which would be better than none. Or, you could get a gro-pight - Lowe's carries them for about $15, bulb included - and put it on the table. I've used them that way before when there was no way to hang one above something that needed more light. Side-lighting isn't ideal for sun-loving plants, but they seenm to adapt. You might then have to rotate the plants so they grow straighter - a quarter turn a day seems to keep my phototropic plants relatively straight next to a window.

Pleasant surprises are always better than the other ones!