It's pretty easy for a plugin to hang the client, if the author is malicious.
It is also quite easy for a plugin to cause a brief "freeze" by simply using the Lua API as intended, which is unavoidable. (LocalPlayer.GetAttributes can take several seconds on high-level characters.)
Which four plugins are you using?
Is there any logging I can enable to show plugin interactions with the client or is this something that can only be provided by a plugin?
The latter, unfortunately.