So I tried to play the game in 1440x900, but the game screen seemed to have been 'moved' up as proven by opening the steam menu where a lot of the stuff was cut off at the top. After some fiddling I gave http://oblivion.nexusmods.com/mods/38800/?tab=1&navtag=%2Fajax%2Fmoddescription%2F%3Fid%3D38800%26preview%3D&pUp=1 a try but it only made things worse, quite apart from wrestling with steam this new EXE has caused the issue to spread OUTSIDE the game! My entire screen is now shifted up with a lot of stuff (such as browser tabs, an absolute nightmare browsing right now as I have to guess where my mouse is hovering) cut off at the top and a stupid black bar at the bottom. I've tried resetting my computer, starting the game in a different resolution with or without the "fix", changing my computers resolution, but nothing seems to work. So quite apart from not being able to play Oblivion in widescreen now EVERY program and windows in general has the exact same issue only in EVERY resolution.
EDIT; so I fixed the desktop issue, for some reason my refresh rate was changed to 60hz from 75 of it's own accord, weird. But I can assume this is what's wrong with the game. Just need to find the option for it now...