What would be the shortest and optimal method of extracting human cells for PCR? Is there a colony PCR like protocol for human cells?
I am not confident in my reply, but the article linked below has methods for DNA extraction of various human sample types( blood, hair, urine, Cheek)

For what its worth, my professors always told me DNA extraction was more of an art than a science, and one has to tinker to get it just right. 

Maybe for something really quick, you could try a protienase K "squishing buffer" and then boil it for like 10 mins in the buffer and then try running PCR.  I am just an undergraduate though so take my words with a heavy grain of salt.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3792701/

Here is how they gathered the buccal samples:
buccal swabs:


  five healthy adult volunteers were recruited (age range, 22–35 years),
  and demographic information, including age, health condition, sex,
  population ancestry, hair color, and hair treatments, was collected.
  The volunteers recruited were asked to rinse their mouth with tap
  water, 30 s before sampling of buccal swabs, to avoid the
  contamination as a result of food particles. For each individual, both
  sides of buccal mucosa were wiped with a cotton swab for 15 s, and a
  total of five samples was collected in 500 μl 10 M Tris-HCl, 10 mM
  EDTA, 2% SDS, containing 1.5-ml microcentrifuge tubes. Isolation of
  DNA from cotton swabs was performed.


Here is a copy paste, hyphens are mine.

DNA Extration:


  Buccal swabs:
  
  -samples were suspended in 500 μl lysis buffer [10 mM Tris (pH 8.0), 10 mM EDTA, and 2.0% SDS], and 50 μl 10% SDS, followed by 5–10 μl 20
  mg/ml proteinase K
  
  -incubated 1–3 h at 56°C until the tissue was totally dissolved
  
  -The DNA was then extracted from each sample with an equal volume of phenol:chloroform: isoamyl alcohol solution (25:24:1) and mixed gently
  by inverting the tubes for 3 min.
  
  -samples were then centrifuged (Eppendorf 5415R; Hamburg, Germany) for 10 min with 10,000 g (4°C),
  
  -upper aqueous layer was transferred to a fresh, sterilized microcentrifuge tube.
  
  -RNase A (10 μl of 10 mg/ml; Fermentas, Thermo Scientific, Germany) was added, and the solution was incubated at 37°C for 30 min. 
  
  -Equal volumes of chloroform:isoamyl alcohol solution were added and centrifuged (Eppendorf 5415R), again with 10,000 g (4°C) for 10 min. 
  
  -The upper aqueous layer was transferred to a sterilized microcentrifuge tube, and double the volume of chilled isopropanol
  (Merck, Whitehouse Station, NJ, USA) was added, along with one-tenth
  volume of 3 M sodium acetate, and chilled at −20°C for 1 h for
  precipitation.
  
  -After 1 h, the sample was centrifuged (Eppendorf 5415R) at 10,000 g (4°C) for 10 min.
  
  -After decanting the supernatant, 250 μl 70% ethanol (Merck) was added, and the pellet was dissolved; the mixture was centrifuged at
  10,000 rpm for 10 min, and the supernatant was decanted gently.
  
  -The pellet was air-dried under laminar air flow, and the dried pellet was resuspended in 50 μl nuclease-free water or 1× 10 mM Tris-HCl, 1
  mM EDTA, pH 7.6 (TE), buffer and frozen at −20°C or at −80°C for
  storage.