I tend to agree with what Harper has been saying.
If you're going to charge flat fees I'd recommend them not being on site, rather at your house/office/whatever. It is NOT worth the trouble of driving out (gas and wear on your car) and having somebody breathing down your neck the whole time and for virus/spyware removal it's likely to be a long job. For on site stuff charge an hourly fee. In the Mpls/St Paul area rates are about $80/hr, so I guess you could charge half of this.
Drop the SOuth Park character, it looks cheesy. Also definitely drop the ex-Geeksquad thing and mention your numerous qualifications (A+ Certified, X years of experience in repair, etc.). This will sound a lot better.
Also have your customers sign a work order (so they understand and agree to the work you'll be doing), a disclaimer (so you're not liable for crap going wrong that's not your fault), and have them before you begin. Don't lift a finger until they pay. Also use receipts and keep records. This stuff will save your @$$ I guarentee it.
Lastly avoid printing this flier on plain white paper, it makes it look unprofessional. Print it on light yellow or something so it catches the eye better.