I did “The McDonalds Thing” when I first started University and needed some work to pay the bills.
It wasn’t that bad a place to work. The girls on the registers were pretty hot, and after about 6 months I deliberately got myself transferred onto the Front Counter so I could hit on… er, talk to them. [Glen Quagmire] Giggity Giggity Giggity![/Glen Quagmire] 
Anyway, the things I learnt were this:
I. Yea, thou shalt smileth unto yon Customers, and agree wholeheartedly to their outrageous demands.
II. The food doth lacketh Nutritional Value, but verily, it doth be affordable and stomach-filling.
III. The Product Level shall never be correct… Yea, for there shalt be a glut of Product when the Customers art lacking, and there shalt be a want of Product when the peasantry come calling in search of sustenance.
IV. Thou shalt not have sex with the Hot Front Counter Girl that the Assistant Manager has his eye on.
V. Thy Managers art picky about yon Uniform, and Yea, there shalt be no Uniforms in yon size.
VI. Verily, the smell of French Fries shall permeate every article of clothing and every pore of yon body.
VII. No matter how many hours thy toil, there shalt never be sufficient coinage by way of remuneration
VIII. The Angry Female Crew Trainer that hates everyone probably IS a lesbian.
IX. Thou shalt not suggest said Angry Female Crew Trainer join thyself and the Hot Front Counter Girl that the Assistant Manager has his eye on for an evening of sinful debauchery.
X. To quoteth Jeff Foxworthy: “No matter how crap your job is, someone, somewhere is doing something involving Hot Tar for $5 an hour. So just remember, when your job sucks, think: Hot Tar, $5 an hour.”
You’ll probably learn a whole bunch about teamwork, and in all honesty, it’s not that bad a place to work.
The biggest problem you’ll have is realising you’re a Burger Lackey at McDonalds, but if you can get past that, it’s not that bad.
For the record, I also worked at Burger King (at the same time I was at McDonalds, near the end of my time there) and I have to say McDonalds beat Burger King hands down as the place to work.
Has anyone seen that movie Waiting…?
Working at Burger King was exactly like that. It was uncanny, actually. Without the party at the end, though. 
In your interview, remember to stress your love of customers and all things customer service related, previous food experience, and desire to stay with the company long term (even if this is a blatant falsehood).
And just remember: You could be working ankle deep in faeces all day. Someone has to. 