DirectX 3D???Follow

i put a new hardrive in my computer like a week ago because my old one got destroyed with viruses. so on the new one its like Windows XP Professional which i have no idea if thats good or bad, but right now it kinda blows! i downloaded some random programs then popped in my FFXI disks downloaded them all wasted like 4 hours of my life; after that i went to go log in so i clicked on it, and the game was all disgusting looking like it was dotty and slow as hell!!! so right from that i knew there was a problem. i finaly got to the screen on POL that lets u play and i clicked play and it didnt go into full screen mode which i kind of figured and said i need DirectX 3D which i dont even know how to get that... im just going to get a new computer or something when i get money eventually but if anyone can help me with info or something that would be cool till then.

ps: thanks for responding if you do, sorry for all that writing above and extremely sorry for my spelling its extremely bad!