Uninstalling leaves database behind - feature

I would like to try running my site without komento and discuss that were installed previously. I dont really have buy in and these are slowing my site. I know they are getting optimised but until they do I want to remove the scripts that are getting called and reduce the plugin tax too.

So I have found that disabling the component doesn't really help - seems not to really do what I expect as if you disable a module and the plugins probably still run. So can I uninstall my current version and then just install later on the latest version or do I need to know what version was in ?

And is the data lost on uninstall ?

Thanks