Naini lake
himalaya darshan view point
snow point(u have to take ropeway)
khurptaal
sariyatal
tea garden shyamkhet
naini devi mandir
pangoot(18 kms from nainital beautiful way) I would suggest u to go to ranikhet(I have been there 3 days back along with nainital u can check my photo blog)... the way to ranikhet from nainital is amazing and u will get a clear view of himalayas from there.
Boating in Naini Lake for sure, else you can visit Naina devi temple
Gondola ride (if open)
Bhimtal
kainchi dham
Take a short trek to the view point route or else you can take a pony also.
In nainital, you can visit the following
•Naini Lake
•Nainital Zoo
•Camel's Back
•Naina Devi Temple
•Naina Peak
•Pangot (For bird watchers)
•Himalaya Darshan
•Tiffin Top
•Aerial Ropeway Nainital
•Kilbury
•Eco Cave Gardens
•AERIES You can take a taxi to visit all these places..