for AA (Anti Aliasing) you can edit enbseries.ini

this lines:

from

[ENGINE]
ForceDisplaySize=false
ForceAntialiasing=false
ForceDisplayRefreshRate=false
ForceAnisotropicFiltering=false
MaxAnisotropy=16
AntialiasingQuality=2
DisplayRefreshRateHz=60
DisplayWidth=1920
DisplayHeight=1080
ReflectionsForceHighPrecision=true
ReflectionsExtremePrecision=true
AntialiasingUpScale=1.0


to

[ENGINE]
ForceDisplaySize=false
ForceAntialiasing=true
ForceDisplayRefreshRate=false
ForceAnisotropicFiltering=true
MaxAnisotropy=16
AntialiasingQuality=2
DisplayRefreshRateHz=60
DisplayWidth=1280				< Your Width resolution
DisplayHeight=1024			< Your Height resolution
ReflectionsForceHighPrecision=true
ReflectionsExtremePrecision=true
AntialiasingUpScale=1.0


Enjoy :P