Try this Word podcast from a couple of weeks ago http://www.wordmagazine.co.uk/content/its-wedding-music-podcast-with-gue...

then Beautiful Sunday by Daniel Boone will result in this

Usually played about an hour and a half or so after you start, so that they have had a chance to get a few drinks in.

worth a search.
groove is in the heart should appear sometime in the night though.

Can I also recommend Respectable by Mel and Kim? It's never let me down...

See above.....

There are several 'accidental' DJs among the Massive so you'll find a wealth of good advice to be found here.

First things first, there is no such thing as a 'serious music crowd' at a wedding. They're quite a tough gig since you've got a cross-generational crowd who all want their favourites, and it being a wedding expectations and emotions are exceptionally high. Drink will have been taken.

A few golden rules which I've learned from doing it myself, and from the wise words of the Massive:

1. Makes sure you've got the right equipment for the job (simple but easily f**ked up)

2. Make a playlist but be prepared to rip it up.

3. Get the girls dancing and the men will follow.

4. Take some requests but don't let them dominate the night.

5. You don't have to go for the lowest common denominator, nobody expects the Birdie Song any more, you can play cool stuff like Teenage Kicks, Echo Beach by Martha and the Muffins, Specials 'Gangsters' as a long as you play some dance and pop stuff too.

6. Mix up the genres as much as you can, but try and avoid crunching gear changes. Play 2-3 of a similar style before bridging into something else. 2-3 Motown Hits can segue nicely into 'Hey Yah' by Outakast and hey! now we can play some modern pop hits.

7. Before you get to the smoochie numbers slow things down with some big sing-along anthems, try 'Can't take my eyes off you', 'Never Forget' by Take That, 'New York New York'.

But enough of my yakkin...the wisdom of the Massive:

Try these threads for start:

http://www.wordmagazine.co.uk/content/help-im-going-dj-a-wedding
http://www.wordmagazine.co.uk/content/wedding-tunes
http://www.wordmagazine.co.uk/content/guaranteed-floorfillers
http://www.wordmagazine.co.uk/content/im-dj-ing-a-wedding-and-they-want-...

and this podcast:
http://www.wordmagazine.co.uk/content/new-podcast-where-kylie-works-and-...

Good luck and let us know how you get on.