Drive Belt I have 98,000 miles on my 2000 MPV. Should I change the drive belt just to be on the safe side?

If you remove the A/C compressor and don't make the needed changes for the serpentine belt to still be installed, then no it won't be safe ot drive. You won't have any power steering for one and that would make turning the wheels extremely difficult. Since the water pump also need the sepentine belt to operate, your engine will overheat in a short amount of time.

belts should be changed every 60,000 miles or 5 years max so it is due a belt anyway.
if the belt does come apart it will do serious damage to the valves , head and pistons.

i would change the water pump at the same time for peace of mind. especially as it will be exposed while doing the belt, and you do not know if the pump is seized/worn.

it is always preferable to adhere to the maintenance schedule. engine damage could result.

REMOVAL & INSTALLATION Because serpentine belts use a spring loaded tensioner for adjustment, belt replacement tends to be somewhat easier than it used to be on engines where accessories were pivoted and bolted in place for tension adjustment. Basically, all belt replacement involves is to pivot the tensioner to loosen the belt, then slide the belt off of the pulleys. The two most important points are to pay CLOSE attention to the proper belt routing (since serpentine belts tend to be "snaked'' all different ways through the pulleys) and to make sure the V-ribs are properly seated in all the pulleys. Although belt routing diagrams have been included in this section, the first places you should check for proper belt routing are the labels in your engine compartment. These should include a belt routing diagram which may reflect changes made during a production run.

1. Disconnect the negative battery cable for safety. This will help assure that no one mistakenly cranks the engine over with your hands between the pulleys, and that the cooling fan cannot activate while servicing the belt(s). NOTE: Take a good look at the installed belt and make a note of the routing. Before removing the belt, make sure the routing matches that of the belt routing label or one of the diagrams in this book. If for some reason a diagram does not match (you may not have the original engine or it may have been modified), carefully note the changes on a piece of paper.
   
2. For tensioners equipped with a 1⁄2 in. (13mm) square hole, insert the drive end of a large breaker bar into the hole. Use the breaker bar to pivot the tensioner away from the drive belt. For tensioners not equipped with this hole, use the proper-sized socket and breaker bar (or a large handled wrench) on the tensioner idler pulley center bolt to pivot the tensioner away from the belt. This will loosen the belt sufficiently that it can be pulled off of one or more of the pulleys. It is usually easiest to carefully pull the belt out from underneath the tensioner pulley itself.
3. Once the belt is off one of the pulleys, gently pivot the tensioner back into position. DO NOT allow the tensioner to snap back, as this could damage the tensioner's internal parts.
4. Now finish removing the belt from the other pulleys and remove it from the engine. To install:
   
5. While referring to the proper routing diagram (which you identified earlier), begin to route the belt over the pulleys, leaving whichever pulley you first released it from for last.
6. Once the belt is mostly in place, carefully pivot the tensioner and position the belt over the final pulley. As you begin to allow the tensioner back into contact with the belt, run your hand around the pulleys and make sure the belt is properly seated in the ribs. If not, release the tension and seat the belt.
7. Once the belt is installed, take another look at all the pulleys to double check your installation.
8. Connect the negative battery cable, then start and run the engine to check belt operation.
9. Once the engine has reached normal operating temperature, turn the ignition OFF and check that the belt tensioner arrow is within the proper adjustment range. Fig. 1: Often the underhood label will display the serpentine drive belt routing
   Fig. 2: Relieve the belt tension by pivoting the automatic tensioner away from the belt, then remove the belt
   Fig. 3: Verifying serpentine belt alignment in the pulley
   Fig. 4: Fig. 1 Accessory V-belt routing (alternator) — Mazda MPV 3.0L engine
   Fig. 5: Fig. 2 Accessory V-belt routing (power steering) — Mazda MPV 3.0L engine
   Fig. 6: Fig. 3 Accessory V-belt routing (A/C compressor) — Mazda MPV 3.0L engine
   

60,000 Miles also your van is an interference engine which means if timing belt breaks will cause major engine damage ( bent cylinder head valves ) and cylinder heads will have to be remove to replace bent valves.

If the timing belt breaks it could cost you alot more! If it breaks the pistons can slam into a intake or exhaust valve and bend them. This action could also crack the piston. If this happens an engine re-build will be required plus it could leave you stranded somewhere. It is possible you could drive another 30,000 miles without a problem...but do you want to take the chance?

most vehicles today are recommended to change every 90,000 to 100,000 miles, Good Luck!

75,000 miles for heavy urban city driving.
100,000 miles if you drive a lot of freeway.
Mix driving should be under 90,000 miles.
If your the timing guide (on the side of the timing belt cover) making noise then you should change it ASAP.
A loose timing belt will offset timing on the injector and decrease mileage.

you really only need to change them if they are squealing or cracked up badly.

no you cant drive without it.