A 64 bit OS is not the same thing as a 32bit so it wouldn't be an option on your current copy of Vista. You would have to buy a separate 64bit copy an it typically isn't cheap. I replied below under the premise that you wanted to stay under $100. Otherwise there would have been other recommendations. I would consider extra RAM and a 64bit OS as an upgrade option when you plan on spending more than $100 bucks.