Need some small security consulting? It's just as simple as that paragraph read well and after these actions!
1) You must install an anti-virus (Avast - Free). [Anti-Virus advisor] (Links in French)
2) You need to do a defrag every week (Ccleaner). [Software Advisor] (Links in French)
3) De-install any software and program you no longer need.
If you follow these instructions you should have a slightly faster than normal PC, so do not hesitate to give your opinion or advice etc. ..