High ping and low FPS are two different things...
Ping is related to your internet connection and FPS is related (mostly) to your computer hardware.
Regarding your ping problems, do 2 things and post the result here.
1) Go to http://www.speedtest.net/ and run the test.
2) Go to command prompt (start - type cmd is the search box) and type "tracert 208.167.243.207" (without the quotes).
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Added - I just re-read your post and realize I misunderstood the comment about FPS - so ignore that part of my response.
Also, I realize you're asking for advice about what to buy - but let's take a quick look at the problem to see if that's the correct solution before spending the money!