First. Try using Optifine. Second. Add more RAM to minecraft by editing JVM arguments in minecraft Launcher. You can find it in Edit Profile. If it sill will lags your Minecraft than throw this notebook through window and go buy something better.
Try use optifine, gamefire and turn off browser and some ram-expensive apps. Also u can give to Minecraft more RAM. Notebooks not for gaming, i think..
RE: i have problems with the lag, when i playing minecraft