I have Vista Home Premium with 2 gigs of ram and an AMD Dual-Core 4000+, and the runtime for CS3 from opening it to having it fully loaded is about 6 seconds. Never lags, runs smooth with no glitches, so I don't know what your problem is.

Just try to do some normal maintenance on your machine. Do a Registry Sweep first of all, that's usually the biggest problem with lags and crashes. If that doesn't help, try to Defragment your Hard Drive, and see if that'll do it.

Give us an update.