How do you say this in Japanese?
 

I realise it's rude to immediately start asking questions without introducing myself or becoming an active member first, but my sheer frustration has caused me to ignore those moeurs. So please excuse me.

How would you say "What do you want me to say?"

I thought maybe this:
Anata wa watashi ni nani itte o hoshii desu ka?

But "hoshii" is only for objects, not verbs, right?

Is it:
Anata wa watashi ni nani itte o shitai ka?

Or perhaps it's:
Anata wa nani itte o watashi ni shitai ka?

Please, if you don't mind, explain why the answer you gave is the correct one. Especially the particles; I find it hardest to grasp them.

Much appreciated.

あなたが私が何と言うことを望みますか

I can't read kanji; could you please write that in romanji?

This is so not what Japanese people would say. I'm guessing you're in your first year of Japnese. Am I correct? You haven't learned てほしい constructions, and you haven't learned proper usage of は／が or the preference for not using あなた.

They would say something like
なんと言ってほしいですか。
Samples from database of natural Japanese: “you want てほしい”の検索結果（146 件）：英辞郎 on the WEB：スペースアルク

Please... Romanji.

Follow these simple steps and you'll never have to write that again:

1)Get the Firefox web browser here.

2) Download and install the Rikaichan plugin for Firefox here.

3) Download and install one of the dictionaries for Rikaichan here.

4) Open Firefox and turn on Rikaichan by either right-clicking the screen and selecting Rikaichan from the menu or click the little circular icon in the lower right-hand corner of the screen.

And, done! When Rickaichan is on, just hover your mouse over a Japanese word and a dictionary entry complete with hiragana pronunciation will appear. Of course, that isn't romaji, but it sounds like you know hiragana, so you'll be fine. And this is all free, by the way.

I'd already done steps (1), (2) and (4) and was wondering why it didn't work; it was because I'd missed step (3).

Thanks!

Why is "と" the correct particle?

And can ほしい always be used with verbs? I thought it was only for nouns and maybe adjectives.

Also, because you didn't specify "you" and "me", couldn't it be read as "What do I want to say?" For reference, how would you say the same sentence with "you" and "me" included?

Thanks.

No problem!
と is the particle usually used with いう (to speak/say/etc.).

て-form of a verb plus ほしい is used when A wants B to do something. ほしい is already an adjective, so it can't be used directly with another adjective. Noun plus が plus ほしい is used to indicate someone wants some thing.

I think of と as the "quotation" particle.
〜と書く = "to write 〜"
〜と読む = "to read ~"
〜と言う = "to say ~"
〜と呼ぶ = "to call/term ~"
etc.

〜てほしい means "to want someone to do something"
Have a look at examples: “てほしい”の検索結果（1285 件）：英辞郎 on the WEB：スペースアルク

No. "What do I want to say" is, first of all, a really weird thing in English, so it's hard to imagine how to translate it. Personally, the only time I'd use that phrase in English would be if I were speaking, then stopped to ask myself "what exactly ought I say right now?" In that case, なんと言ったらいいのかなぁ〜 or something. But this does not mean "What do I want to say?"

It's hard to answer this question because translation is about converting what is intended in one language to another, not about turning one word into another. If someone says "Honey, can you do this?" You don't translate honey into the Japanese word for bee vomit even though that is what the "honey" means, literally, in the English sentence (you're calling your spouse a sweet-tasting food). Instead, you might say あなた in Japanese, which just means "you," but can carry a connotation of lovingness between spouses. Something like "Dear" or "Honey."

With "you" and "me" included, it would probably sound like bad, unnatural Japanese. 〜さんは私がなんと言ってほしいですか。 Literally, it's something like "As for [you, Mister ~], you want me saying what?"