Buy a flat bead scanner for film, theyre anywhere from like $125 to upwards of a few thousand for top of the line, canon makes some cheaper end ones. If thats not an option soon enough then you can always take your negatives to a photo place and have them scan them onto a disk.
As for resizing images in photoshop you really shouldnt have any problems if you just click image and click images size. The only way youre going to havea problem is if youre attemping to resize an image bigger than the original size.