Here are a few things that made my simming more enjoyable...

Fly IFR with some flexibility:
Setup your normal IFR flight plan (in FS2002 or your flight plan application, this does not apply to adventures), then when ATC hands you off acknowledge the handoff and 'tune center', but DO NOT 'contact center' - you can now fly any altitude or route and when ready 'contact center', they will resume communication and vector you in to the airport selected in your flight plan.

That wing leveler pissing you off? There are several free utilities to turn it off for you but all they do is add this to the [autopilot] section of your aircraft.cfg file...
use_no_default_bank=1
use_no_default_pitch=1

RADIOS and AUTO-PILOT:
Having problems with radios and/or the autopilot? Try putting this in your aircraft.cfg file in place of whatever is there...

[Radios]
// Radio Type=availiable, standby frequency, has glide slope
Audio.1=1
Com.1=1, 0
Com.2=1, 0
Nav.1=1, 0, 1
Nav.2=1, 0, 0
Adf.1=1
Transponder.1=1
Marker.1=1

[autopilot]
autopilot_available=1
flight_director_available=1
default_vertical_speed=1800.0
autothrottle_available=1
autothrottle_arming_required=0
autothrottle_takeoff_ga=1
autothrottle_max_rpm=95.0

**
default_vertical_speed=1800 is for Jets with some power, for the C172 use 500. Popular figues are 500 to 700 for smaller piston props, 1000 to 1500 for medium turbos and small jets and you can go as high as 2200 if you have the balls to maintain speed at that rate of climb... Additionally you can set it at 0 and adjust it from the autopilot when you are flying.

autothrottle_max_rpm=95.0 can also be adjusted if you seem unable to maintain max speed when the autopilot is on, really 80 or so is default but I go from 90 to 100 to assure throttle is there for steep climbs and obtaining max speed in flight.
**

PANELS:
Getting good panels for a plane is hard, they may not include all the gauges, the plane may not be compatable with the panel (gauges don't work ect) or FS2002 warns you about bad 3rd party gauges and/or crashes when they are used. BEST TIP: set the properties of your GPS.GAU to READ ONLY, this prevents older or incompatable versions of the GPS from overwriting your working FS2002 GPS and ruining your day. I try to get FS2002 packages of both plane and panel - also watch for them using PRO gauges if you have the standard version (Concorde, King Air and perhaps other gauges are not included in the standard version so you will end up with a panel that is missing gauges).
If downloading tons of panels and doing the trail and error thing is not for you then whip out 25 bucks and get FSPanel Studio, it is easy to use and lets you modify or make your own panels...
Additionally you can simply alias to a plane with a similar panel, but what fun is that?

SOUND:
The sounds included with FS2002 are nice, but there are more and better ones - especially if you do not have the Pro version. Aaron Swindle is the man when it comes to sound, search for his name in the sound sections of sites like SurClaro or the other bigger sim sites. He has some upgrades for the default sounds and new sounds with startup and shutdown sequences that are real nice.
There are many other people who make sounds, and tons of sound files out there - however I like to have startup and shutdown sequences and a lot of the sound files out there are not for FS2002 and/or do not include startup and shutdown sounds. Really the default jet sounds can be applied to most any jet, it is the turboprops and piston props that you may add that need a 'proper sound' and I have found Aarons to be the best of the ones I tried - and I tried a lot of them.
Alias info:
Piston Props will use the c182/sound or for high end machines try the extra300/sound, the F4 also can be used for some older Piston Props. The c208/sound is the turboprop sound. The lear45 is the smaller jet sound and the 737 is the default heavy jet sound - in pro the kingair is the bigger turboprop sound.