teceem: I'd replace those 5,400rpm HDDs with an SSD. Although the main reason the OP mentions is to play old games - those slow HDDs will make them feel really sluggish.
Considering he wants a laptop under $350, investing in a SSD just increases the price, or then he would have to get some stupid 125GB SSD that will be full in no time.
Also, to this day I still don't understand how some of you people praise SSD, as if it makes everything feel sooooo different.
I have now two gaming (capable) laptops. One has old 5400rpm HDDs, the other has a 256GB SSD. The games play the same on both, the only difference is the loading times. I simply couldn't care less if it takes 2 seconds or 10 seconds to load up a game. That is the only difference you will see while playing game, for having a SSD, yet some make it sound as if "upgrading" to a SSD is the biggest upgrade you could ever do for your gaming PC. I wrote "upgrading" because to me it feels more like a downgrade, as big SSDs just cost too much so one has to go with some measly 256GB SSD, unless they are ready to pay an arm and a leg for it.
SSDs just aren't worth the extra price for gaming, period. The more extra room you get for the same money by buying a HDD instead makes much more sense.