Can you take a free action and a standard action as part of a ready action? Suppose I ready an action to attack the first monster to come into melee range. When one does I take an attack - can I also shout, cast a quicken spell, or use some other action?
Using a strict reading of the ready rules (see page 160 of the Players Handbook), the answer is no. While the ready action allows you to combine a 5-foot step as part of the ready action, it doesn't say anything about allowing free actions.
Furthermore, the first sentence of the second paragraph under the Ready heading ("you can ready a standard action, or a free action.") seems to support this, as it clearly sets up a free action as one of the three options, rather than including it as an addition to be included along with either of the other two options.
Since speaking is generally defined as a free action you can perfome "even when it isn't your turn" (see Players Handbook page 144), you don't need to combine a shout with the readied action. You can simply perform it any time you want, including right before or after taking a readied action. The same is true of any spell (or action) that you can cast (or perform) when it isn't your turn, such as casting feather fall, or any spell with a casting time of 1 immediate action. (editied for content) Your couldn't cast a quickend spell, though, as that can't be done when it isn't your turn.
Dragon Magazine 328, Sage Advice page 81.