Can you switch a video from time lapse mode if it has already been shot?

No. Time lapse takes one picture every whatever interval you set. For example, one picture every 10 seconds. Nothing is recorded for the 9 seconds inbetween so no software program can make up what was supposed to be there.

Sorry, no.

Unfortunately, no. Time-lapse video works by taking fewer frames and then displaying them at normal speed so as to give the impression of time going by faster than in reality. Thus, the camera simply hasn't recorded all the information it would have in normal mode, and there's no way to recreate that information. Think of reading just the first line of every page of a book: you'd get through it quickly, but you'd also miss some things.

Now, if you'd shot in slow-motion, then you could throw out some frames until you got to normal speed.

Oh my, sounds like you accidentally recorded in "Time Lapse" mode (one of the specialized video features of your camera). Unfortunately, there's no way to convert the already taken video back to "Standard" video with sound, I'm sorry. However, you'll obviously need to set your camera back to standard mode for future videos. Press the "Function" button while in video mode. Then press left/right to select "Standard" video.

This is a really simple problem and easy to solve.  Unfortunately the videos you've recorded cannot be changed back because they have been recorded in Time Lapse mode.  
With the camera switched on in Video Mode turn the control dial on the back (this is the dial to the right of the LCD screen).  This will change the settings from TIME LAPSE to STANDARD.  There are actually 6 different modes but the best one for normal videos is STANDARD.  There is a HIGH RESOLUTION setting,  however these record fewer frames per second (fps) so whilst the quality is better per frame,  there are half the amount of fps so the the movie will look at bit jerky.
It's really easy to accidentally twist the dial when holding the camera,  so always check the icon in the top right of the LCD before recording to make sure its just a yellow camera in a yellow square.  
This should be problem solved for all future recordings.

This is a really simple problem and easy to solve.  Unfortunately the videos you've recorded cannot be changed back because they have been recorded in Time Lapse mode.  
With the camera switched on in Video Mode turn the control dial on the back (this is the dial to the right of the LCD screen).  This will change the settings from TIME LAPSE to STANDARD.  There are actually 6 different modes but the best one for normal videos is STANDARD.  There is a HIGH RESOLUTION setting,  however these record fewer frames per second (fps) so whilst the quality is better per frame,  there are half the amount of fps so the the movie will look at bit jerky.
It's really easy to accidentally twist the dial when holding the camera,  so always check the icon in the top right of the LCD before recording to make sure its just a yellow camera in a yellow square.  
This should be problem solved for all future recording.

This is a really simple problem and easy to solve.  Unfortunately the videos you've recorded cannot be changed back because they have been recorded in Time Lapse mode.  
With the camera switched on in Video Mode turn the control dial on the back (this is the dial to the right of the LCD screen).  This will change the settings from TIME LAPSE to STANDARD.  There are actually 6 different modes but the best one for normal videos is STANDARD.  There is a HIGH RESOLUTION setting,  however these record fewer frames per second (fps) so whilst the quality is better per frame,  there are half the amount of fps so the the movie will look at bit jerky.
It's really easy to accidentally twist the dial when holding the camera,  so always check the icon in the top right of the LCD before recording to make sure its just a yellow camera in a yellow square.  
This should be problem solved for future recordings.

This is a really simple problem and easy to solve.  Unfortunately the videos you've recorded cannot be changed back because they have been recorded in Time Lapse mode.  
With the camera switched on in Video Mode turn the control dial on the back (this is the dial to the right of the LCD screen).  This will change the settings from TIME LAPSE to STANDARD.  There are actually 6 different modes but the best one for normal videos is STANDARD.  There is a HIGH RESOLUTION setting,  however these record fewer frames per second (fps) so whilst the quality is better per frame,  there are half the amount of fps so the the movie will look at bit jerky.
It's really easy to accidentally twist the dial when holding the camera,  so always check the icon in the top right of the LCD before recording to make sure its just a yellow camera in a yellow square.  
This should be problem solved for future recording.

No. Time-lapse video is recorded at a much lower frequency than regular video. The information between recorded frames is gone.

Imagine taking a picture out of your office window once an hour. You might catch some cars moving and/or people walking, but you won't be able to see what happened between the pictures.

You can go the other way, from a regular video to a time-lapse video by skipping frames. Unfortunately you can't do the opposite without guessing at what happened in between.

Select RCA camcorders feature both an Automatic and a Manual recording mode. Automatic recording places the camcorder into Auto Shot™ mode. Focus, exposure, iris control, white balance, and the video light are controlled by the camcorder during Automatic recording. This mode is particularly handy for those times when you want to be able to just point the camera and record. The Manual recording mode allows you to control many of the elements above yourself, as well as many of the camcorder's special features including Animation and Time Lapse. Manual mode is also where you access the menus and set the clock. Make sure you press in the LOCK button while setting the POWER switch to the desired setting, either "A" (Automatic) or "M" (Manual) record mode.