On my other computer, it works fine, but on this computer, when i try opening up limewire, the main 'signing in','opening', ect screen doesn't come up, it just acts as nothing.
i've tried re installing it, firewall isnt blocking it, i don't know what to do.

Try opening it directly from the LW program folder. The shortcuts might be corrupt. If still problems then try deleting your LW Preferences folder whilst LW is closed; instructions here: Fixes for Limewire If still problems after that, then try uninstalling your Java & re-installing it. But better to install the java from your comp., not over the net.