Help with my Japanese?

Hey everyone,
I was hoping you guys could help me with my Japanese!!!! XD

Firstly, here are some words/phrases I need to know how to pronounce. Don't worry if they don't
make sense by themselves, that's probably just because I know how to pronounce the other parts!!!! :O
Here they are:

Doozo
Aa
Soo
Gozaimasu
Anata
Daisuki
Konban wa
Oyasumi
nasai
Doomo
Sumimasen
onegaishimasu: i would also like the meaning of this word and when to use it please!!!! 0.0

Thanks, I'm pretty sure I know how to say them but I thoughtI'd double check!!!!
Secondly, I need the meaning for some other words/phrases. Again, I think I have the idea but
I need to make sure that I am correct!!!! =)

Desu: I think I have a pretty good idea of when to use this, but can you give me a less-obvious
example of when NOT to use this word?!?!

Daisuki: I think this means something like "like very much" or something along those lines, but
I think it can also be romantic-like. Is that true? For example, I think this makes sense:
"Watashi wa anata ga daisuki desu" - I think this means "I love you" or something?!?!

Watashi wa: Can this be used by both males and females????
Watashi wa (name) desu: Is this commonly used or is "(name) desu" better????

Anata: Can this be used in any situation????

Lastly, could you please help me out by providing some information about 'double-vowels' and
'double-consonants'?!?! I REALLY need help with this part because I can't pronounce them right???? 8)

Also, if there are any words/phrases I have asked about here that aren't really
used anymore/are oldfashion,could you please let me know?!?! Thanks for all your help- My
Japanese really isn't THAT bad, I just needed to double-check!!!! Er, arigatoo?!?! :P

When it comes to pronunciation, if you have the five vowels right (a, e, i, o, u), you can't go wrong - it's somewhat difficult to explain *how to* pronounce without knowing what difficulty you may be having with those words :) The same goes for "double vowels" and "double consonants" (do we have any double consonants??).

onegaishimasu
This phrase means "I ask of you," and it can be used when you ask someone to give/sell you something, either as the verb, or as "please":
- Koohii wo onegaishimasu. (I would like to have some coffee please.)
- Koohii hitotsu, onegaishimasu. (One coffee, please.)

Desu
The prime example of when TO USE it would be when you say "I am..." to introduce yourself, so you can tell it's like "be-verb" in English, right? For something this general, it's difficult to give example of when NOT TO USE :)

Daisuki:
Yes, "suki" means "like" and "dai-suki" means "like very much." As the Japanese word for "to love" can sound VERY serious, yes, people use "daisuki" to mean romantically liking/fancying someone as well.

Watashi wa: Can this be used by both males and females????
Yes.

Watashi wa (name) desu: Is this commonly used or is "(name) desu" better????
It's not that either one is better than the other; if from the situation it's obvious WHO you are talking about, you can omit "watashi wa." For example, if you approach a hotel counter where you have a reservation, the staff there asks you "your name please?" then you can say "Smith desu."

Anata: Can this be used in any situation????
I don't quite understand your question... but generally when speaking in Japanese, we don't really use this "you" pronoun, because it really "points at" that person. Among friends and acquaintances, it's more the norm to use their names (plus -san) or nicknames instead.