Do you have access to this computer?
Third-hand info about computers that none of us can see...can tend to make troubleshooting a bit tedious and very inaccurate.
<<Sometimes when she cuts the computer on, it doesn't boot all the way, it gets stuck like halfway.>>
Any error messages? Does it shut off or does the screen just freeze? If the screen freezes...at what point does this occur?
<<When she can get it to boot up, it's extremely slow and takes programs a long time to load.>>
Can she boot into safe mode minus these symptoms? But the programs do load? How much free space on C: partition and how large is C: partition?
<<She says that her computer is unable to connect to the internet anymore, and other computers in the house can connect with ease.>>
<<Sometimes the computer will freeze up while she's performing a task on it.>>
Any error messages onscreen? How about errors reflected in Event Viewer?
Worth reading the comments by Quietman7, IMO:
Slow Computer-browser Check Here First; It May Not Be Malware - http://www.bleepingcomputer.com/forums/topic87058.html
EDIT: Since you have access to other computers...you can remove the hard drive from the troubled computer and attach it to another...and run malware scans, see how large C: is, how much free space, etc. The more info that you can furnish, the better and more valid member suggestions can be made.
Edited by hamluis, 29 October 2010 - 12:05 PM.