Sonic the Hedgehog/Crash Bandicoot (especially the reptiles), Spyro the Dragon, Rayman the...Rayman, Super Mario (sorta...), Fur Fighters, Studio Ghibli, Stitch, other Disney animation, Rango, reptiles in general
Lex Lang (and Jess Harness with just a year less) are less jarring to me because their characters (and especially their tone) have been kept pretty consistent the entire time they've voiced them. Greg Eagles from the Titans stuff to N Sane Trilogy is like getting Eggman from Sonic X to Sonic 06.
Debi Derryberry's been on the series the longest and her voice for Coco goes in and out through the course. She went from feminine and soft spoken to basically her Jimmy Neutron voice to slowly leaning back into the former.