Brian,
Carbonite and Mozy are both decent solutions but 100 to 200 Gig of data is a lot of data to back up online on a regular basis.
That brings to mind a couple of questions.
1. Is the majority of the data media related, as in music and or video?
2. Do you have an older pc sitting around or access to an external usb drive?
If the majority of your data is music or video, these are files that really don't change all that much as a rule. An external USB drive locally would be a simple quick solution in that case. You can use the built in Windows Backup utility or any number of free backup programs found online to do this with relative ease and without intervention on your part.
If that volume of data is actually information that changes frequently then odds are pretty good that you're going to end up paying a monthly fee. Amazon S3 cloud services is also an option here for the volume of data you're referring to. Byte for byte, this may be a possibility as well given how much data you seem to have.
The second pc question was with regards to repurposing the pc with something like NASLite or a network share established. Internal hard drives (or external for that matter) are cheap solutions for backing up that much data without a monthly expense.
If the data you're referring to is business related and has any confidential material or personnel data, there are serious security considerations you have to account for as well. Again, a local solution is ideal for this. If you store confidential data online, then you should seriously consider encrypting your information with something like Truecrypt.
