well i would but it apparently freezes my whole computer up and i have to do a force shut down... i don't think i have enough ram to run it... which really sucks... gonna do some updates and what not to clean the computer up and see if that works.. did the last time i did all that... so fingers crossed...
It would help having some system specs to start from...
Generally speaking, modern packs require a few things. The biggest is 64-bit hardware with a 64-bit OS and 64-bit Java. This is due to the inability of a 32-bit system to support more than 4GB ram, even without OS-imposed limits (Windows only allows 3GB by default, for example, and older versions used 2GB for OS tasks leaving 1GB for Applications).
A 64-bit CPU can still run 32-bit OS and software but shares the memory limits of a 32-bit CPU when you do because the software was written on the older hardware... In addition, you might have 64-bit Hardware and a 64-bit OS but be running a 32-bit Java, with the same limitations in effect.
If you have these first 3 requirements then you need to have enough ram installed to run the packs. To start with, Windows requires up to 2GB ram reserved for itself (more for older versions). If you have Integrated Graphics, like a cheap motherboard or most laptops, then you will have up to an additional block of ram for exclusive video use, usually 256 to 512 MB. Separate GPU cards usually have and manage their own separate memory.
Due to changes in Java, packs newer than 1.10 will need a minimum of 4GB to run on the lowest settings, up to 6GB to run nicely. More if you want to use shaders. Previous versions ran well on less ram.
To sum up, taking Overhead needs into consideration (OS, video ram) plus 1.10/above versions of Minecraft, I would try to have at least 8GB ram in my system. 6GB would work if you could buy 3GB ram modules but 4GB are more common and hence cheaper. Most systems will have a minimum of two ram sockets.
Tl;dr: Get more ram, maybe?