Hi Bubbles,
In HijackThis put checks next to the following then hit fix all:
O2 - BHO: (no name) - {02478D38-C3F9-4efb-9B51-7695ECA05670} - (no file)
O2 - BHO: Yahoo! IE Services Button - {5BAB4B5B-68BC-4B02-94D6-2FC0DE4A7897} - C:\Program Files\Yahoo!\Common\yiesrvc.dll (file missing)
O9 - Extra button: Yahoo! Services - {5BAB4B5B-68BC-4B02-94D6-2FC0DE4A7897} - C:\Program Files\Yahoo!\Common\yiesrvc.dll (file missing)
O9 - Extra button: (no name) - {CD67F990-D8E9-11d2-98FE-00C0F0318AFE} - (no file)
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) -
Going by what MBAM and SAS are saying, you have a rootkit that combofix should be able to remove.
Download here:
https://www.techspot.com/downloads/5587-combofix.html
or here:
http://www.forospyware.com/sUBs/ComboFix.exe
When saving combofix to your PC, rename it to 123.com so malware won't disable it. Launch combofix (now titled 123.com), allow it to download and install the Recovery Console if it prompts you. Once the scan starts, DO NOT TOUCH YOUR PC, clicking anywhere while combofix is running is enough to make your system become non-responsive. Be forewarned that combofix will make your desktop dissapear and will also reboot your PC as needed. This is normal.
Once combofix has run, run MBAM again as well as HJT.
Post logs when done please.