Cant change settings in win 98

yesterday my computer running windows 98 froze, when i restarted i discovered it had wiped my mouse drivers and who knows what else, also it changed my display settings to 16 color and the screen area to 640×481 pixels which makes for annoying and hard viewing, when i try to change them it demands that i restart, after restarting i find that no changes have been made at all, please help as the 16 colors and tiny screen make for hard use.
Thankyou
Houston