Disabling VM will not help. In fact it can prevent some programs from running. Most of the info put into VM is stuff windows is not using. If your playing a game, the game will not be in VM but other programs that don't need to be running can be put in VM freeing up more memory for your game. So in a way disabling VM makes your system use more physical memory then what it needs to.
Do a google search and your find many sites that have ran tests and have found no or very little benefit from disabling VM.
In task manager you can see what programs are using VM and how much. Goto view and select the columns you want.