not sure what skybot is ( not heard of that one ) but could be spyware or viruses , also what is starting up with your machine ( you can check by using msconfig or start up control panel --> www.mlin.net ) If you can disable or stop items starting up with your machine then do so, just make sure they are not system items such as your graphics card etc.
avg anti spyware, spybot search and destroy and anti spyware personal are some good anti spyware apps.
Avast and avg anti virus are good anti virus apps, obviously make sure for both anti spyware and anti virus that all there anti virus / spyware update defintions are up to date before you run a scan.
I would highly recomend not to use system restore, I normally disable system restore before doing an anti virus scan as the virus will keep putting itself back otherwise.
Once you have compltely cleaned it out and you are happy with how it is running then you can re enable system restore if you wish.
Depending on how much time you want to spend on this, it sounds like backing up all your data first and making sure you at least have the network card drivers ( so you can at least get back online and get the latest drivers for all your hardware ) would be adivisable.
That would most likely be the easiest thing to do.
also if you could post back with a spec of your machine ie how much ram, what cpu you have etc.