Nissan: Key Problems

Howdy folks,
The other day someone tried to break into my car, a 1990 Nissan
Maxima. Nice old car with 154000 miles on it;works well and hasn't
given me any serious problems. Well,nothing major happened when he/she
tried to break in. I think the security alarm must have gone off or
something. So everything inside was fine. No body damage. But in the
attempt,both the driver and passenger side keyholes got screwed. So I
am not able to open my car by plugging in the key. I did however
manage to find a way to get into the car. The trunk keyhole's fine and
so I open the trunk push forward the rear seat handrest and use a long
pole to open the backdoor lock. I know. I know. Very clumsy. No
wonder, I 've been staying up at work till 11 PM!
Now, trying to think of a solution, here's what i considered. I
wouldnt want to replace the keyholes with the risk of it being a
victim of a prank again. I also had a look at some keyless entry
systems available online. Some from AudioVox,Bulldog. I also dont
wanna spend too much on the car right now since I am looking at buying
a new car some months from now. Plus the Bulldog (KE100 I think) is
avaialble at buy.com for $30.
To make it easier for the gurus here,I have listed some questions
which I would love to have some insight on.
1. Is installing a keyless alarm the right choice in my current
condition? Or rather, is it even viable .I am especially curious about
this since I wonder if while installing the keyless kit,the security
alarm will go off. It has happened before when I needed a jump start,
but then I just locked and unlocked the car with my door key. Now with
my door lock disfunctional, I am not too sure. I read somewhere that
inserting the ignition key(the ignition and door keys are separate for
my Maxima) into the ignition keyhole works. Also, an interesting point
is today morning while I was doing the
creeping-into-trunk-opening-door routine the alarm did go off. What I
then did was shut the trunk and unlock it again with the door key. It
worked!
2. I would be the first to say that I dont know much about cars.
Considering that is self-installing a kit like the KE100 doable for
someone like me?
3. Should I be considering some other options which I obviously am
not aware of?

I apologize for the long email.
Thanks for your time and patience.

Help!
Shravan

Paul Simonite <co.uk> wrote in message news:<co.uk>... 

Thanks Paul. Although not directly related to my case, any info is welcome!
-Shravan