We've just come back from Menorca. We booked through First Choice and stayed at the Mar de Menorca in a 2-bed apartment (five of us). There were 6 beds - two in each bedroom and two sofa beds in lounge area) so I would imagine you can book for six in one room.
The hotel was 3-star all inclusive. Great adult/older children pool, and a kids pool with small slides. 10 mins walk to a beach - very small beach, but able to swim in clear blue sea.
Food was good quality and varied. It is buffet style for all meals. Ice creams/pastries/drinks all inclusive all day.
2-bed room was plenty big enough for us (3 adults, two pre-schoolers). I would imagine you'd be fine with 2 adults and 4 under ten. Six adults would be a squeeze! No bath though, just a shower.
There was pool side entertainment during the day that the 10 and 8 year olds would enjoy, and a kids disco in the evening that your 2 year old would enjoy (plus face painting!). There was also a kids games room with ping pong and some (need to pay for) ride on things (racing bikes etc). There's also a toddler room with organised activities for an hour per day with a member of staff, but you can take your kids in there yourself during the day too.
15 min bus ride to capital town, Mahon. We went for a morning and walked a bit then went on a road train thing that toured the town stopping for 10 mins or so at interesting places. You can also do things like a glass bottomed boat from Mahon.
All in all, a relaxed low-key holiday. Not a great deal to do except swim in sea/pool and take part in the activities if you fancy, but enough to occupy young-ish children for up to 2 weeks. Weather was great too (early to mid September) and I would imagine would be good into October :)
Hope you find something :)