I downloaded Oblivion GOTY form Impulse and when I try to play it opens the launcher. After I click on Play it says Loading... for a few seconds then disappears. Nothing happens afterwards. I am using Windows 7. There are no mods or anything like that, just the game. Is something wrong?

No one here can attempt any answer. If you actually have a PC version (yes, I know Windows 7 doesn't run on an Xbox360), you've omitted any useful information to work with. Only console game versions can be dealt with in as simple of a form as you've attempted so far.

Minimum System Requirements:

* Windows XP, Windows 2000, Windows XP/64-bit
* 512MB System RAM
* 2.4 Ghz Intel Pentium 4 or equivalent processor (XP 2200)
* 128MB Direct3D compatible video card and DirectX 9.0 compatible driver;
( ATI Radeon X800 GTO, NVIDIA Geforce 6800 GT )
* 8x DVD-ROM drive
* 4.6 GB free hard disk space
* DirectX 9.0c (included)
* DirectX 8.1 compatible sound card
* Keyboard, Mouse

Post your dxdiag

I got the game to work by using Oldblivion. I don't know why that would work, but the game doesn't seem to have any more problems.

OldBlivion was created to answer for nVIDIA's official lying to its customers. Neither the low end Geforce 6n00 cards, nor the entire generation of nasty FXes were good enough, and not even the EXTRA LOW end settings added to the game worked for the FXes, other than "somewhat" for the two fastest of those. OldBlivion swaps out the Dx9 textures for Dx8 textures.

Fixed.
OP,you might be better off buying a new video card.Oldblivion was never properly finished(AFAIK),and as a result has a lot of graphical glitches which may spoil the game for you.

If the OP's comment about OldBlivion is factual, there probably is no real video card (Intel chips don't meet the definition), just a very elderly onboard graphics solution of some sort. The Geforce 6600 and lesser nVIDIA cards are now seven years old, minimum, and the Radeon 9200 / 9250 are eight years old, all of those as AGP video bus products.

I was only using Oldblivion to start the game, I didn't use it to make any actual changes. Anyway, turns out the real problem was that my antivirus software, Webroot, wouldn't let me run Oblivion, so Oldblivion never really fixed anything, just made me turn off my antivirus.