Straghitening for dummys

I am a long time user of Photo Paint 12.  Not a "power user", just rather pedestrian jobs.  One is to straighten scanned item -- I can never get them exactly square on the scanner bed.  For this I have been using a VB macro, MCRotator.  All of this running Windows XP.

But -- I am just moving to Windows 7, and Graphics Suite X7.  And, MCRotator will not run on W7, the code is locked, and the programmer is, as far as I know, dead.

I was under the impression that PP X7 would give me some sort of equivalent function, but I am yet to find it, and I find the discussions on "straightening" in these forums impossible to follow.

For those who don't know it, MCRotator worked by drawing a rectangular mask with diagonally opposite corners on the ends of a line which was to be made horizontal.  One drew the mask and chose the direction of rotation, and the macro computed the angle and did the job.

I have tried the straightening tool, but having to line things up by eye is much more work, and much less accuracy.

So my question is: is there any way to preform this operation with the ease and accuracy of the defunct macro?  If there is, please explain it in words of one syllable or less, and don't assume that I know much more than drawing masks and manually cropping.

Yours, hopefully