Any of the high value but limited application spells are handy on a scroll. Things like Cure disease, Neutralise poison, Restoration, Zone of Truth, Locate object and so on. In other words, spells that are awesomely useful but only get used once/3 months or so, even if you always memorise them. An added condition for scroll spells is that you normally need a full round to use them (minimum). Put spells that you would commonly use in non-combat situations or to recover from combat effects.
I also strongly strongly recommend a Heal spell or other Cure Level Appropriate Wounds as an emergency backstop. This one should be given to the Rogue, or someone with massive UMD skills in case you get taken down. This goes double if you are the only effective healer in the group.
Magic Circle against Bad Stuff, Water Breathing, Freedom of Movement, Knight's Move, Mass Resist Energy etc should be memorised. If and when you need these ones you need 'em in a big hurry.