If you are using one of the Title Animation Presets, then you will need to increase the Duration of that Title (click+drag on its Tail), to slow down the Animation.
I perfer to NOT use Title Animation Presets, and instead, Keyframe the Fixed Effect>Motion>Position, to get my Animation. Then, I have complete control over the speed, and can even pause the Title's Motion, if desired.
I am new to all this, but happy with my attempts so far. I'm sorry, but I don't understand what you mean by Keyframe. I can't find "Fixed effect" It is not on the effects menu. I am using the preset and increasing the duration of the clip only got me more black space the credits still flew by.
Here is a little bit of background.
Each Clip, that is dragged to the Timeline, has certain Fixed Effects, that are automatically added to it. Those are accessed from Edit Effects, with that Clip Selected, from the Effects Panel. Those Fixed Effects are: Motion (with two sub-Effects: Position and Scale), Rotation, Opacity and, if that Clip has Audio, then Volume.
Keyframing of an Effect, whether one of the Fixed Effects, or an added Effect, changes that Effect over time. Not every added Effect can be Keyframed, but most can.
The change in the Effect, whether one of the Fixed Effects, or one that you have added, is controlled by adding and adjusting Keyframes. Steve Grisetti has done a great, multi-part series on Basic Keyframing in PrE, at Muvipix.com.
Keyframes can be added to, and adjusted from several locations, for Fixed Effects, like Motion>Position. One can change the Keyframe Display of a Video Track, to show those for each of the Fixed Effects, or one can go to Effects>Edit Effects, with the Clip (your Title) Selected in the Timeline, and do the Keyframing there. I like the latter, as I am working in the Effects Control Panel, rather than in the display of the Clip in the Timeline.
Note: the initial concept of Keyframing Effects is a bit abstract, at first, but once gets that concept down, a great deal of power is unlocked. Also, every minute spent learning Keyframing will pay dividends, due to their power. That is why I so strongly recommend Steve's Basic Keyframing, as it gives one a good start on both the concept, and on the mechanics.
Stretch your title longer on your timeline.
The longer your title, the slower it will roll/crawl.