Getting back into riding but still a wimp at this point. Have Raleigh M60 and TREK 800, upgrading the TREK to 8300 possibly. I know it's old but prob not older than my Raleigh. Need advice.

1st owner was avid trail rider and 2nd owner rode once a year ago.

Bike seems in great shape, has all the bells and whistles. Any thoughts, advice?