So im debating on which 840 evo to get, the 120gb or the 250. a friend of mine told me to go for the 250gb and expand the storage later on, but i will most likely only need windows and a few games on the ssd. the 120gb would be better because i will save money buying a 1tb hdd or 2tb hdd for my music/games etc.
I personaly have a 120 GB ssd(kingston hyperx 3k, really loving it) and a 2 terra disk 5900 rpm(4 years old or so, moved it into my newish pc from my old one) my ssd has 53 GB free disk space(it's been like 5 month so it seems this is how it will remain) I have my os on it+browsers and a few programs that I use everyday(which are worth the ssd space)
On my old 2 terra (which is 5900 rpm, I assume yours would be 7200 which is faster) ALL my games are on it. If you have enough ram, your disk will load files once, then even if you are not using them, windows 7/8/vista would keep them in memory, and the next time they need to be loaded they are already there. In short when playing a game from hdd, you only need to suffer through the first loading screen. And if it is a game you play often you can always keep a copy on ssd, then delete that copy from the ssd when you are bored with it and keep it on hdd.
240 GB ssd is not worth it, I doubt it is. And you need a place to keep your music and photos etc... and if 120 GB ssd was not enough, a 240 would not be enough either.
My page files are on the hdd, not because I am worried about wearing the ssd(well I am, but that is not the main reason) but because page files assume they are on hdd anyway and go through the extra effort of becoming a sequential read...