回复：我觉得必须换掉旧的内存，现在只有1.5G可用

Win32 can only manage 3.x GB RAM. So even if you upgrade to 4GB, not much of the added would be used anyway by your vista. I had an SSD installed on my desktop (C300 from Crucial. I am using it now on my notebook). It improved the performance drasticly, especially for photoshop etc. Applications launch almost rightaway and win7 starts in 20 seconds. Read the reviews on newegg or amazon. You'd better to use SSD under Win7 though, as Win7 has built-in TRIM for SSD maintanance.