I have been looking on the Internet, regarding the the ceiling level of the flying altitude of a Cessna.

Cessna makes many aircraft, from trainers to jets. They have different
ceilings. Most can go above 10,000 feet (although some may take a while
to get there!).

I know that Cessnas' are not pressurized and, the ceiling level could cause her to have a bad headache.

Some are, actually. Voice your concern to angel flight, and to the
pilot. If there are no mountains to get over, and the weather is good,
then the flight can be made at a low altitude. In your case, you will
need to cross the Appelatian Mountains, which can get up to several
thousand feet, but there are (longer) routes that can take you around
them if necessary. The northerly route looks promising and can be done
below four thousand feet. Airplanes don't have to be operated at their
service ceiling.

Pressurized aircraft are often pressurized to about an 8000 foot equivalent.

Take a look at
http://www.runwayfinder.com/
and put the airport codes for the airports you wish to use, separated by
commas, and hit RETURN. You can plot a route that zig zags by listing
more than two airports, separated by commas. Once that's done, you can
even switch to other google views (the site is powered by google maps).

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.