I am thinking of installing a higher resolution texture pack, probably skyrim 2k. However, i am not sure if my fps is going to be affected and if so, by how much? Will the FPS be decreased like SSAO used, or 4x AA?

Currently i am using no texture packs, just vanilla skyrim on High(default) settings. I also use an ENB which takes away 5-10 FPS at max.

As long as you have adequate VRAM it shouldn't reduce FPS as drastically as enabling AO or even 4x AA on most single cards setups.

There are also lite texture packs you can try for a good balance of performance and quality.

oh i m not worried about vram issue, just FPS and perhaps a bit of loading time. Thanks for the quick reply