cant change colour resolution

well i don't know what has happened but the colour resolution has gone to the lowest (640 by 480) and i cant change it i tried loads of stuff and nothing seems to work it was fine up til now i havent done anything i recently uninstalled some things on the computor so something might have been uninstalled but i dont know what also the icons and everything has gone really big and it wont let me change that either.

You probably need to reinstall your graphics drivers.

They can be found on your graphics card manufacturer's web site.

but i don't know what my graphics card manufacturer's web site is :S.

Can you go back to a restore point before you uninstalled things?

From this link (you will link to another link) read this section as to ID your graphics card:

[3.1.1.1] Collecting Video Card Information