Unless you're a complete idiot (in which case please click on the shiny little X in the corner), or you didn't read the title, you'd realize justGeorge's Pokemon of the Week is Lugia. I like Lugia personally. He used to be really awesome. Unfortunately, Ho-oh is also gaining popularity. I hate Ho-oh, but he has a nice signature move. You can't deny that a 50% chance of burn is a nice touch to an already powerful move. Aeroblast doesn't quite compete with that, but it still has a high critical hit ratio.
Below are some uses for that Guardian of the Sea, Lugia.
Calm Mind Lugia
Roost / Recover
The goal with this guy is to create an undentable, unbeatable, unfeintable, and inescapable beast that will eventually sweep your entire legendary team (except for those that resist him like Dialga). The problem with this set is that it's weak to critical hits and super-powered moves in the beginning. If you can handle that, go for it. Just watch out for those nasty-plotters.
Rain Dance Party Lugia
Roost / Recover / Protect / Thunder
With the huge amount of people creating Rain Dance Parties, you know it will move toward Legendaries too. Lugia can very easily slip into a Rain Dance Party and wreck havoc on those puny Pokemon. Unfortunately, Lugia is weak to Thunder. All Kyogres have them, and they're sure to be in Rain Dance parties. So, Lugia is best used after Kyogre dies, preferably later to sweep the team.
The last move is really up to you. You may want a recovery move, just 'cuz Lugia is a defensive Pokemon. Or, you may want to use Protect because of so many Surfers, plus this tactic only makes it more annoying when you have Leftovers. Thunder is just an awesome move, all around. And during rain dance, it may become necessary.
Choice Specs Lugia
I wouldn't advise giving Lugia Choice Specs, just because it's way too risky. However, you may catch quite a few people of guard, especially when they assume you will start boosting your stats first with Calm Mind.
This moveset has nice type coverage, but it still doesn't make Dialga even flinch. That bugs me. Lugia doesn't learn any good fighting moves. That is one pitfall for him (and his large amount of common weaknesses).
This brings me to the How to Whup Lugia section of the Pokemon of the Week.
How to Whup Lugia:
Dialga is a strong choice against Lugia. Lugia can't do any damage against the Time Pokemon without Calm Minding, at least. Also, you could use physical super-effective attacks like Volt Tackle, Ice Punch, Thunder Punch, etc.
Essentially, Lugia's downfall is his lack of move variety and huge amount of common Legendary weaknesses.