I'm sorry Clare but if you cannot provide more information than that, then it is hard to help. That is probably why you have not received any other replies. TT people are happy to assist but we do not have unlimited time to cover all options. You need to narrow it down for us.
My guess is that you want to do day walks with a group. If that is the case then:
Lucerne, I assume you mean a city tour. They are easily booked at the tourist bureau. You could also walk up Mt Pilatus or book a group tour, e.g.: http://www.viator.com/tours/Lucerne/Mount-Pilatus-Summer-Day-Trip-from-Lucerne/d576-3885SW304BSL
Lauterbrunnen, links to various walks: http://mylauterbrunnen.com/en/Holidays/SUMMER/Hiking
Wildschoenau, try: http://www.wildschoenau.com/en/guided-walks-programme
Lake Como, the Greenway is the day walk to do. I doubt if there are guided day walks. Try Google.
Grunau im Almtal, no idea, contact ATO at holiday@austria.info
If I am wrong then please answer my questions if you want help!