There, that oughta do it! :O)
Sorry, it's like 5am. I've got nothing... :O)
Buy as much ram as you can. It can be added later, but it is much cheaper to buy it new because of (a) installation costs and (b) one usually has to discard the old ram to install the new, so that upgrading to 1gb means buying 1gb and discarding the 512mb you already have.
If speed is imperative, consider asking for a 7200rpm hard drive. It will shorten time between recharging, but it will really boost speed.
There, that oughta do it! :O)
Sorry, it's like 5am. I've got nothing... :O)