problems after installing 64bit can i go to 32bit?

ok first a little of what i have done. I have an older computer amd athlon 64 3200+ 2ghz and i originally had 1 gb of ram installed. I was running windows xp pro and i decided to get win7 pro. I have 3 hd's and i want to have a dual boot system. I installed w7pro 64 bit on one of my secondary hard drives. It seemed to run ok except i know i needed more ram. I installed another 2gb of ram and now i am getting blue screen crashes, and i ran the memory checker and it says i have memory problems
I get this when it crashes
Problem Event Name: BlueScreen
OS Version: 6.1.7600.2.0.0.256.48
Locale ID: 1033
Additional information about the problem:
BCCode: a
BCP1: FFFFF7FF82A10644
BCP2: 0000000000000002
BCP3: 0000000000000000
BCP4: FFFFF8000289B89B
OS Version: 6_1_7600
Service Pack: 0_0
Product: 256_1
Files that help describe the problem:
C:\Windows\Minidump\011810-71046-01.dmp
C:\Users\AmAIN\AppData\Local\Temp\WER-135000-0.sysdata.xml

ok so i am going to take out the extra memory i put in and try it again but in the mean time here are a few questions.
with my current processor/memory, would i be better off going to the 32bit version, if so i have both versions of the disc included, can i just format the drive and install the 32 bit version and revalidate it?
i am having problems finding pc3200 memory.

ok i ran the memory test with the original 1gb of ram and it came back as no problems found so i am guessing the memory i bought will not work with my computer. I think i read 2gb was the minimum memory for 64 bit. My friend has 2 512 chips i can get from him, would that be enough to run 64 ok. i dont game, i just surf the net, do a little video editing,

Welcome to the forums!

2GB is the minimum you'll need for x64, but it does sound like your memory is faulty so I would get a replacement. Did you purchase the correct spec RAM?

You can format the drive and use the 32-bit version with 1GB ram no problem, however it will work much better with 2/3/4GB .

ok thanks for the info. I posted in another section about maybe upgrading my whole system.

Download this attached file below, unzip it and burn to a CD-RW and use it to boot from on a restart.

It's MemTest v4.0 9-22-09 version.

It loads from DOS and does an excellent job of checking your memory with no other systems running.

Webpage is HERE