What have you set your resolution to on the PC?
Try 800 x 600.
The TV would only be 420 x340 (or somthing like that).
edit - I was thinking the Tv as being an older analog and not a new LCD. In that case, the resolution of the TV might not be able to go as low as 800 x 600 therefore you are getting the blurry effect.
What model is the TV?
According to the feature list the "Tesco Technika LCD32-209 32in LCD TV " is not PC capable, and its native resolution is 1366 x 768http://www.trustedreviews.com/Tesco-Technika-LCD32-209-32in-LCD-TV_TV_review_feature-table_Page-4