Want to start a entire new set of backups after, loosing a couple days of Backup.

I run a similar setup here. I have two external USB drives. On one, I run MWF, and the other I run TuThSa. I also run a periodic Sunday Files-level backup as well as several cloud backups and syncs. I think having two drives gives you some redundancy. You never know when one may fail. This may be overkill, but if it's important to you, it just is. Or if you're like my case where a second drive comes along... I would definitely use more drives if you have them available rather than just backup to one. You've already had one external USB drive fail. If the drive you are backing up from also fails, your second external has you good to go. Definitely start over with a new backup routine for the MWF drive. Find the current routine in the list, change its schedule to "Do not schedule."

Then

Click OK. Now that you've disabled the old routine, create a new one. Click "Disk and partition backup" at top. Select the source drive. (I prefer to do disk backup rather than partition backup as that backs up everything, including partitions that aren't easily seen). Choose what you want to call it, and choose a new schedule. Then choose a cleanup routine.

A few tips: 1) If things don't go well, it's usually best to start over rather than edit old routine. 2) Save only one routine per destination directory.

I'll create a video and post it.

OK, the video is at:
http://screencast.com/t/Ot7fdqiV4n

In this video, I create a disk backup for Monday, Wednesday, Friday. This is a differential backup, keeping two diffs before making a new full. Three chains are kept. Ideally, this would mean 1 full per week and two differentials, with three weeks of backups kept before deletion.

1) From Backup and Recovery tab, click on "Disk and partition backup." I prefer to switch to "Disk mode" to catch all partitions.
2) Choose your destination directory. In my case it is a directory on an external USB drive. This forum suggests best practice is that each routine has its own destination directory.
3) I create a new folder and call it "NEW MWF 2013." Call it anything that makes sense to you. By default, the backup file name is the name of the drive. You'll probably want to change this to something that makes sense to you. I call mine "NEW_MWF_2013_DISK" in this example. Acronis will append file chain info to this name. This file name does not have to match your backup name in the UI, but it makes things less confusing. Click OK.
4) You can see that in the Settings box of the Disk Backup screen, the Backup Name now matches the file name. You can change this, but again, I think it makes things confusing if they don't match.
5) Click on the Schedule link and a "Schedule your operation" window will open. Select the days you want to backup. In this case, it's 3 times a week, so I choose weekly, and choose Monday, Wednesday, and Friday. The time is often difficult for me to set for some reason. I click in there, and it won't let me type, and so if I can get close, I go with it. I turn OFF the missed backup feature. In my case, this usually only happens when my computer is turned off, and nothing is worse than turning on my computer and finding several missed backups trying to run. My policy was, if the backup is missed, it was missed because there probably wasn't anything new to backup anyway.
6) Change the backup type. I like differential, but you can use incremental. Remember, if you use incremental, and any of your diff chain breaks, you have to go back to the one just before the bad backup.
7) Decide how many differentials you'd like before making a new full. Then select how many to keep. I did 2 differentials and keep them for 3 chains (so three weeks). **Remember, you have to have enough room to keep one extra backup.** Backups are made, then the cleanup process deletion occurs.
8) Take a peek at advanced options. Among the features here is a password protection. If you're taking disks off-site from an employer, this would be a good option. REMEMBER THE PASSWORD!
9) Take a peek at notifications. I usually turn on email notifications, but uncheck the box for sending notifications on successful completion. That way, I only get emails when the backup fails. That option is under "Additional notification settings" in the lower right, and I do not show them in this video.
10) Exclusions can be helpful if you have files that don't really need to be backed up. For example, if you have a browser's download directory full of large installation files that you could easily download again if you need them you could exclude that directory or *.iso or *.msi. Or maybe you have virtual machines that you don't need or could easily be recreated, you could exclude *.vhd or *.vdi. For myself, I have some routines that exclude *.MP3 because I have those files mirrored to another drive.
11) At the bottom, choose the little arrow next to the "Back up now" button. Pull that down to "Later" and it will take you to the main screen.
12) You may not see your backup right away because the "Star" at the top filters on "Favorites." Turn the star off, find your newly created routine, and then click its star. You can then turn the star filter back on.