For basics, Beguiler 1/Wizard 4/Ultimate Magus 10 (or however far you get) is by-far the best choice. Beguiler 2/Wizard 3 as entry is not going to get you killed or anything, but it is a dramatic loss of power relative to only a single lost wizard level.
Cloaked Casting
From an optimization perspective, Cloaked Casting isn’t nearly worth what you lose in terms of wizard spellcasting.
Unfortunately, Cloaked Casting is rather minor in general. There’s no reason you can’t surprise your opponents with your spells, and just not get the +1 DC bonus. Surprising people is usually a pretty good idea anyway (though feinting in combat is not). You will be better off doing things this way.
But feel free if you really want Cloaked Casting to get it. Just be aware that it will cost you more than it ought to.
You don’t have to ban Illusion if you don’t want to
Wizards get illusions that beguilers don’t, and your wizard spellcasting will be superior to your beguiler spellcasting. If illusions are important to you, keep it on your wizard; having it on both classes will really play up its importance to your character.
So illusion could be very valuable to you; don’t ban it just because you think it will be redundant. It won’t be if you use it right.
You really don’t need area-damage
Conjuration and illusion are excellent at battlefield control, which means rather than simply damaging people in areas, you’re hitting people in areas with nastier effects, and stuff that warriors cannot do. Damage is easy, and lots of classes do it as well, if not better, than spellcasters. In a lot of cases, though, that’s all they can do. So let them do it.
And ban evocation.
Metamagic
Go for it! Ultimate magus gives you powerful abilities that allow you to use your second class to power metamagic for the first, which works very well. Definitely a good choice.
Shadow Spells
Ideally, you do not want to use shadow evocation or shadow conjuration offensively, because you give the enemy two chances to save, which is bad. As such, I don’t really suggest relying on them for that; they’re massively better as buffs or what have you. Spell Focus (Illusion) is still a solid idea though.
There are no specific rules vis a vis how a character starts combat. D&D5E attempts to avoid that kind of specificity when basic logic and reasoning will do:
- If the character is hanging out in a tavern, his hands are empty... or full of food. Utensils are Improvised Weapons, by the way.
- If the character is hanging from a chandelier, at least one hand very well ought to be weaponless (in so far as one does not wield a chandelier, it had best be making use of one hand).
- If the character just finished picking a lock, his hands are empty.
- If the character just finished picking his nose, at least one hand is empty.
- If the character is dungeon delving and carrying a torch or lantern, he's probably got a weapon in his other hand or has a shield strapped to his arm.
- If the character is dungeon delving and doesn't need a hand for a light source, he'd be smart to have both weapons out.
Either way, it's a matter of common sense and story description, not codified rules.
Best Answer
Seeing as the combat is in hand the bard could focus on doing something non combat related. Some suggestions are:
Otherwise as others have said Ready an Action, Delay etc and hope the situation changes. In our party if the bard had nothing to do he would start singing of our great achievements and how we are going to win this battle or some other roleplaying colour.
Sometimes you just need to accept that there is nothing constructive this turn you can do, try and set yourself up for a better position next time, think about what would have been useful to have with you now and make sure that you have it with next time. In 3.5 sometimes the best thing you can do in a combat is pass your turn so that the combat gets finished faster and you can move on to something more interesting.