I'm using the FO2 Hi-Res patch and running at 1680x1050. Now i can see a wide area of the map. However, my toons and everything looks so small. Am i able to zoom in or something while maintaining the resolution?

There is currently no documented fix all for this issue.

there is a mod that will upscale:
http://timeslip.chorrol.com/sfall.html
i haven't tried it myself yet, but from what i understand, this should work.

Actually i already have sfall installed. It works in hand with the hi-res patch but the problem is when running at 1680x1050, everything just looks so small and thats why i'm looking for something which allow me to zoom in.
:)

Why don't you just use a lower resolution? As I understand it the High Resolution Patch really just makes everything smaller, as the graphics can't just be rendered at a higher resolution like it is possible with 3D graphics. Therefore I am just not using the High Res Patch at all to have the original size of everything. Though I could understand the use of this patch if the monitor has problems scaling the picture. But at least for me it really makes no difference and the graphics don't look worse like that or better with the higher resolution, anyway :)

you have to open the ddraw.ini file and set sfall to run in dx9 mode, set the graphics width to your desired resolution, and then pick a scaler that is to your liking. if you haven't messed with the .ini file, then the sfall mod is set to the default of 8 bit fullscreen.

I am using the the DX9 setting which is mode 4. :)
As for the scaler, this is the part where i dont know what each of them does. Also i tried Hardware scaler but i need to find this global.fx file which i tried searching google, found some .fx file and i simply just rename them to global.fx. Not sure what i'm missing though.

here's what you need:
http://falloutmods.wikia.com/wiki/Global_Shaders

illegalyouth, thanks for the links! Appreciate that. :)

no problem. one last tip -- make sure your directx is fully up-to-date, using the latest version of 9.0c. if it's not, fallout will crash at the menu screen.

Thanks. Ya my DX9 is up to date which is the 9.0c version. :)