Gently squeeze the bulbs. If they are soft or have a lot of give, they are too old. Throw 'em away.

Having said that, even if firm and appearing healthy, bulbs that have sat out unplanted for a couple of seasons will produce very poor results, if any. The energy or growing ability stored in the bulb deteriorates with time. The tulips I'd go ahead & toss. They seldom perennialize well even when fresh and I doubt ones more than a year old will do anything.

I'd find an out of the way corner of the garden and go ahead and plant the daffodils now - bulbs keep better in the ground than they do in a garage :-) Next spring you will hopefully see some signs of foliage. You can apply a little bulb fertilizer then and let them go. May (unlikely) or may not (very likely) bloom but if given proper conditions and little TLC they may come back into their own in a couple of seasons.

Thanks.
I'll give it a shot. I have just the spot for them.

hi fmart - i'd love to know how you got on with your old bulbs? i have some now and wondering whether to plant...! Polly

If they are already sprouting top growth, it is hardly worth the candle planting them out - if they survive they will likely be blind...but, could go on and flower the following year. Once the top growth has been initiated (forced, in effect) it will come at the expense of rootgrowth so it is a big ask to expect a plant to do well with few sustaining roots.

with all the time and energy spent in planting bulbs, I don't think I'll go to all that trouble for the probable results being nothing!