My 00 wrangler beeps fast when key turns on and dash doesnt work.

try a jump start as sounds like a flat battery

Normally when ur flasher flash faster only on one side it indicates that u have a light out on that on side could be in front or back turning light

did you RTM read the operators guide yet,
it tells you why all beeps beep and what lamps flash, (warning) and why. did you?
you turn on, the head lights, (what about 1st click , parking lights"?)
and does the dash cluster, show warnings of any kind?

if a door is ajar the system will think, you are exiting veh. with lights on and tell you, buy beeping ,etc.
but on my jeep it says on the dash DOOR, or on EVICs, (not yours)
the newer car even tells what door IS AJAR.
mine on shows , "DOOR"
the operator guide will say, check all doors for ajar, and get warning clear before driving....etc.

if you lost the guide here it is for free

http://justgivemethedamnmanual.com/jeep/jeep-wrangler-owners-manuals/

click the 05 link
ignore beeps, there are just too many .. i look at the cluster and learn to read it..
my newer jeep 08 can produce 1000s of errors,,,,, possible.
in fact the intent it to beep to tell the driver to look at the cluster
for in depth, causes.
see chapter starting on page 136'

once sound it makes is Check gauges chime. so check them.
and headlamps left on
and door ajar.

page 63
NOTE: If the driver's door is left open, and the headlights
or parking lights are left on, the "High Beam
Indicator Light" will flash and a chime will sound.
Lights-On Reminder
If the headlights or parking lights are on after the ignition
is turned off, a chime will sound when the driver's door

its a crude system, and evolved to complex in 2007.
"DOOR" or RF-door , on mine.
or

NOTE: A tone will chime if the turn signals are left on
for more than 1 mile (2 km).

search manual for
"chime will sound"

Sounds like your charging system needs some attention.
1st check battery for voltage should be 12.50 or better with car off
2nd, start car check battery for voltage again should be 14.0 to 14.75 volts.
3 with running turn on headlamps and check charging voltage again if your voltage dropped to battery voltage your charging system is not working.

The ignition key absolutely could have something to do with it. You can probably wiggle it around and get goofy things to happen.

Do you mean 7 rapid beeps and then 2 slow beeps? Google Holden body code 72 then

The beeping alarm would be for leaving the key in the ignition or the lights on. Maybe a gauge that had dropped to zero.
Let us know if it happens again and what the conditions are.

Yes if you check the owners manual you'll find a speed alert function in there somewhere.

check for a bad bulb. this is how the system alerts you to a non-working light bulb.

beeps are warning signs. check: switch lights, seat belts, doors, engine hood, trunk.