95 suburban, ignition locks, can't turn key,

the ignition module (ignition switch on top of the steering column) normally doesn't get stuck.

things you can try:
steering wheel lock: (the pin gets a "burr" on it and locks everything up) wiggle steering wheel back and forth while trying to turn key.

transmission lock (parking on an incline will jam up the interlock)
push the shifter farther into park while trying to turn the key, or wiggle shifter

make sure shifter all the way in park,turn steering wheel back and forth while turning key to lock and remove key, if this works the ignition lock linkage is probably worn and needs replaced

Have you tried sort of yanking the shifter?

your steering wheel lock is connected to ignition in column, pull hard on steering wheel in direction wheels are turned at the same time turn key, this should free them both up.

Well first you should put the key in the ignition and try turning the steering wheel back and forth while trying to turn the key. Next try moving the gear shifter back and forth while turning the ignition. sometimes they will inhibit the ignition from unlocking.

check your key see if its not damaged ok also press the break move the steering wheel slowly and move the key as you are moveing the steering wheel

Try turning the steering wheel (hard) right and left while turning the key. Steering lock , and ignition lock work in conjunction with each other.

the shifter needs adjusting. try to remove the key while moving the shifter back and forth in park.

Keys and Locks when worn will do this as will duplicate keys made not so perfectly. While keeping mild pressure on the key in the direction of removal, jiggle the steering wheel back and forth vigorisly. If you cannot get the shifter into park in oreder to remove the key, same deal, jiggle rapidly. Then see a lock smith

Good Luck!

the battery must have sufficient amount of juice to release the key