Frazzle and FiKelly thanks for the suggestions - we are in Alloa, near Stirling. Where in Tayside / outside Glasgow are you two?
Gleneagles is just over the Ochils hills from us so I may look into it if they are doing some good deals at the mo. Also knew of Crieff but not stayed there - it has a good family friendly rep, but this will probably be a wee overnight away from DS if we can persuade Aunty and Uncle to do the honours.
Re: 3rd Birthday - I hired a local hall for DS in November - they had lots of stuff to play on in one big hall, ie climbing frames, soft spongey stuff etc, with staff that supervised for 1hour and loud music, then they all went into another room that we laid on the food for them - for the other hour, tables chairs provided and plenty run around space. we got lots of balloons, I did all the food which suited us as DS anaphylatic with any milk product, and allergic to eggs and peanuts so it made it easier knowing he could he what he liked for once at a party! - usually i take along a bag of stuff to these parties and dish out as they go.
2hours was ideal - any more would have been too much for everyone. we did pass the parcel and musical statues but that was it.
i think at 3 they just need loads of run around space.