Does this error mean I can't play the game?

[masaofmune]

[Sephirah]

I can't understand the kanji, but it's saying something about Phantasy Star Online 2, your Computer's Opertating system, and the sentence ends in "masen" which is negative. (For example, if you understand something, you say wakarimasu, but if you don't understand something, you say wakarimasen"

[Faendryl]

『ファンタシースターオンライン2』 = ""Fu a n ta shi- su ta- o n ra i n 2""


は、おイ?いのコンピューターのOS = ha, o i ? i no ko n pyu- ta- no Operating System

The ? is in place of the Kanji I don't understand. Also, there is quite a mix of hiragana and katakana in this message picture you posted; I'm sure someone who speaks Japanese could tell you why that is.
I can only figure out half of the rest so I won't bother >.< I hope this helps someone help you.

[Ana-Chan]

The message simply says that Phantasy Star Online 2 doesn't support the computer's operating system.

[Inazuma]

For those learning Japanese and having trouble reading the kanji:

『ファンタシースターオンライン2』　は使いのコンピューターのＯＳに対応していません。
Fantashii Sutaa Onrain2 wa tsukai no konpyuutaa no OS ni taioushiteimasen.