Resizing pictures to 450x450 with Paint
 

First select the picture you want to resize then right click on it and select "edit".
When it has opened select "Resize" See Pic 1
In the Resize and Skew window that pops up select "Pixels" See pic2
Where the "Horizontal" is type in "450" in-place of what was there and the Vertical will auto complete. Then OK it.
Lastly select "Save-as" from drop down "File" menu.
Name the file, select Jpeg or Bmp ( I use Jpeg )
Standard save place is Pictures folder.
I haven`t resized these pics for clarity reasons

I have used this FREE program for 10+ years and it works great.....Irfanview

See: www.irfanview.com

Yeah I use it aswell, just posted for people that are not very computer literate.