Gopi, how you brought them along through winter will determine how well they perform this coming season.

What growth may have occurred over winter is just the result of what kind of sun your window provided. Chances are they received not much...a little, that did foster some growth and you, seeing this, think they'll do OK if just brought along the same way.

They wont. What you see now is the little bit of what the winter sun gave the plants. Not much, not enough to give the plants strength to do a lot more.

So...cut them back to about 4". Remove all the leaves, the flowers if any, unpot the plant, examine the roots and clean them up. Remove all the soil from them.
Pay attention to the branches...examine for any breaks or where immature growth may have started.
Take it back to fresh, clean stem and branches.

A clean pot, to which you place some shards under fresh pottting soil you put in. The pot must have drainage hole/s. Place the plant in, firm it up, give it the best sun you can....south, west, or east.
Water to drainage. Allow full drainage, then dump the excess. Never let the plant sit in that drainage longer than 10 or so minutes.
NOW, don't water again until new leaves form.
No need to fertilize now....the new potting soil will do that.
Turn the plant 1/4 turn every day to ensure all parts receive the same amount of sun.
Within 2 weeks, you'll have a new crop of leaves.
In 4 - 5 weeks, the plant should have a full bounty of foliage and maybe even a flower bud or two---after 6 - 8 weeks. But not to worry, even if they go outside when you put your annuals out, it will flower again...maybe better than ever.

The bringing along like you did this past winter can be done again next year....or, if you have a cool area of your basement, a place where it is dark, cool and dry--your plants can be stored and brought back just as I've mentioned above.
They sit over winter in the dark, in the dryness, in the cool...and come back next March as good as ever.

Thank you for your detailed advice. I'll give it a try

Gopi, the hardest thing to come by is the cool place to store your geraniums. Not many modern homes have such a place-- a place where the heat put out by the furnace doesn't access. Some basements might have a corner that is not as warm but far from cool.
I'm fortunate in that respect because I have a coldcellar--a place much like what farmers have--a fruitcellar--where products are stored over winter for sale in the spring.
I put my preserves there on shelves and in-between put the upside down hanging geraniums. I place a plastic sheet on the floor to catch the debris--and there's lots of that when you go retrieve them.

Cool is a place where the temperature is not much above 50º- 55º. Any warmer than that might initiate growth.

Light too, if in such mild area, will encourage development.
Unfortunately, the growth is slow and doesn't do the plant justice--it is weak and any leaves that might form anew are weak and unable properly to draw light and moisture.

You might be encouraged to think the plant, even as dormant as it is, needs some water--it doesn't.
Water only causes moisture to hang around. Mildew is often the result.

No, the plant ideally is taken out of the ground in the fall and not see light, or water again until we wish it to grow and foliate out like it did the previous summer.
February --the ides of March...that is the time that there is sufficient sunlight to encourage developing new leaves.
Most plants are not like this---they are unable to be renewed. But geranium is in a class by itself--with a few other exceptions-- like pansy--they can be renewed simply by giving them what is needed....warmth, light, and water.

If you cant provide the coolness needed, then don't attempt to do the above--it will only cause disappointment when the plant cant do what it needs to do.
Instead, do what you have been doing, keeping the plant going as long as you can through winter, enjoying what bloom it does provide and then, if you can bring it to February or March, then do the cutting back at that time.
It should do as well.

Wow... great information. Thanks so much.

One further question. I have overwintered a bunch of "geraniums" -- some cuttings and some whole plants. Everything is blooming. The whole plants in particular are spectacular right now -- glorious.

I came here trying to learn how much I should cut them back when they go back outside. Down to four inches and nude was a shock. I'm not sure I can make myself do it ....

I should do it now? And have some growth back before setting them out? Which would be some time in May here, probably/possibly.