Freeing up space on SD card I'm trying to clear some space on my SD card, so I can run AnTuTu Benchmark. Also, having some extra space for music would be great. I'm assuming apps installed to your SD card can eat up free space faster than you'd imagine. As of now, 19 (out of 65 apps) on my SD card which occupy appox. 197 MB total.

I currently have 1.74 GB used and 103.47 MB free, would my ROM be occupying a lot of space (i.e. needing 4GB of HD space to install Ubuntu/Linux)?

I want to figure out the best way to maximise space on my SD card without haphazardly deleting files. Also, knowing what are key folders would help too.
It's better if you don't manually delete stuff, unless you can recognize the package names for the apps you want to remove. 
Though it sounds hilarious to install an app to get rid of apps, APPS2SD will neatly list out whatever apps are on the SD card or can be moved between that and the internal memory, so you can make a list of the apps you don't want and manually uninstall them.

Speaking of key folders, here are a couple of common ones-


DCIM - This stores camera photos.
Attachments - Default save location for Gmail attachments.
download - Default file download location.
data - Stores app specific data. If you have games that download additional data, they may store that here.


This is based off my SD card - most of the other folders I've seen are app specific. 

Update - Some phones have a Camera directory, with DCIM under it, so look for both.