Will flashing a custom fix lag on my Android? I have a 1 GB RAM tablet running a pretty much vanilla Android Jelly Bean 4.1.1 and it's been running very slow. Apps startup time have been slow, noticeable lag exists while scrolling between the home screens, and apps crash sometimes. Browsing on the Internet has scroll lag and I have many more problems. I know that 1GB of RAM is more than enough to run Jelly Bean smoothly without any lag. How will rooting my device or flashing any custom ROMs help? I am new to the Android world, any suggestions are welcome, thanks.
Im not sure about the hardware of your tablet ,so might not be that powerful .That could be the reason for the lag 
About rooting and custom roms they are not assured to remove lag  ,some roms might help while some may be even slower, it depends on the rom You use .But that said generally custom roms are made to be lightweight ,fast and fluid.