Windows 7 - 32 bit or 64 bit ?

I got this computer from someone else. He bought it last summer, but it has never been used. It currently has Windows Vista, but I do not like Vista. I want to install Windows 7, but I don't know wheather to install 32 bit or 64 bit.
This computer is Acer Aspire M3202.
from what I have read, for Windows 64 bit you have to have at least 4 GB RAM of memory? This computer has 3.00 GB RAM of memory, which means I have to install the 32 bit version?

I can buy more RAM? Is that easy? I'm not really computer smart.
I only use the computer for the internet. I don't play games and don't use it for any type of editing. Is it worth while to buy more RAM to install 64 bit when I only use the computer for the internet?

thanks for any help.

 

I have a Toshiba, Win7, 64 bit, 3Gig of memory.

It works great. But I'm not a gamer either.

If you only use it for the internet, like me, 3G with a 32 or 64 bit system will work just fine. In fact, I like to say this is like hauling a bucket of sand with a dump truck, you will come no where near to taxing that system.

 

I'm currently using an older computer with XP. I don't see what bit this is, but I'm guessing 32. I see what I'm using has 1.81 GHz and 448 MB of RAM.
already bought windows 7 which came with both DVD for 32 bit and 64 bit.

The new computer only has what came with it from the store. It was bought last summer and never used. He had it for too long and was not able to return it to the store.

one website I read said once you install the 32 bit you can't install the 64 bit without losing everything. I don't want to have to start all over again if I want to go 64 bit later, but I also don't want to go 64 bit if it's going to cause problems. If 64 bit is better and the new computer can work good for me then I would install that one.