Well I assume that your PC has a slot for sdram. You can't just take out the EDO SIMMs and put SDRAM DIMMs in their place. They're different sizes.
However, if you could put SDRAM in the system, then put in 64 megs and you'll get your performance increase. You claim that 32megs is all you need for that system, but at the same time you're wondering about how to get better performance...so I'd have to say that 32 megs really isn't all that you need.