Hi Neelie amd Welcome to the Forums.
Limewire itself is Safe. Has NO Viruses, Adware or anything else. The issues you're experiancing is coming from the Gnutella Network. P2P means that you are downloading and sharing from other peoples computers, so the Nasties are from other Peers, Not LW.
There is Volumes of info here on these forums that will help you understand what to look out for and avoid becoming infected. However using a P2P program will always be somewhat risky. Make sure you have a good Antivirus program and ALLWAYS Scan EVERY File Before Opening.
Hope this Helps.