I have a problem - I need to enlarge my system partition. I mean - when I initially installed Ubuntu, I split the partition so I have 15GB for system and the rest (around 400) pointed at /home/. This is very useful if anything goes wrong someday and I want to format and completely re-install Ubuntu without losing any of my actual data.

The problem is, 15GB isn't enough, so it seems. I already moved /var/ and /opt/ folder to /home/, adding symlinks at root, but I'm still at 86% usage and I'm having performance issues (mostly when booting or running a VM).

I can use Ubuntu on a flash drive and externally enlarge the partition, but I'm really afraid with going forward with that plan. Also, despite what I said before, I'd like to avoid re-installing the system if at all possible. Any advice, suggestions or ideas on how to best approach this? Any warnings I should heed?

Thanks in advance!

update

Here's the gparted screenshot - as you can see, there's windows on dual boot (sda1-5 are all related to the windows system), then I have a linux swap, 14GB (so uh... not even 15) of system and 435 of for /home.