I took my Ford Five Hundred in for a oil change and was told I was due for a 30,000 mile check up. I was told they did a oil change, changed the air filter. Then I was asked if I wanted to complete the check up I would need to have all the fluids changed at a cost of $425.00, Do you recommend having all the fluids changed at this time, I have 29,550 miles on the car

All the fluids? No. Check your owners manual for fluid change intervals and see what you need. I might expect oil, trans and coolant, but not brake or power steering fluid. $425 seems high for these services as well.

Follow the instructions in your owner’s manual. That’s what it’s for.

Your first mistake was to take your car to a dealer for an oil change. Even if the oil change was “free” it almost cost you hundreds of dollars for that oil change. You were smart enough to question it and to ask. Dealers make lots of money on those kind of add on services.

You will find a list of services that should be done to your car in the owner’s manual. You should have all of those done as listed. (note most will list at least two schedules, one for normal driving and one for severe, situations. Many people fit the severe situation.

There is one service I usually will recommend doing more often than listed in the owner’s manual, and that is changing the transmission fluid if you have an automatic transmission. I would consider 40,000 miles a minimum for a transmission fluid change and filter clean (NOT A FLUSH).

Did the OP take it to a dealer? He/she doesn’t say.

I myself would have the trans fluid and filter changed at 30K miles, but that’s splitting hairs.
I consider the owners manual recommendations re fluid changes to be a minimum.
Changing some fluids more often is OK, and cheap insurance if you DIY.
Here’s the extra things I do more frequently than the manual says:
Change trans fluid/oil every 30K miles
Drain & refill (long life) coolant, change thermostat at 5 years.
Change brake fluid every 3 years.
Drain & refill power steering reservoir each year.
Lastly, use only the carmaker’s recommended fluids.

As others have stated, check your owner’s manual. If your car is an automatic, I’d change (not flush)the transmission fluid regardless of what the manual states. My girlfriends '07 Uplander recommends to do it a 100k which seems insane to me. Some, like the Pontiac G8 state that the fluid NEVER has to be changed. A new transmission can cost as much as an engine these days, so it’s cheap insurance.

You didn’t say whether you took it to a dealer or not, but you’re probably better off going to a decent independent. Have the trans. fluid changed and (somebody help me out here) the fuel filter(s) might not be a bad idea to get done. Ask the rest of the car be checked over. Hoses etc. can deteriorate quicker than you think even if the car isn’t that old so don’t let them miss those.