Been playing guitar for around two years and when i pick up my guitar to practice i end up doing random stuff, that i would think isn't helping my muscle memory etc.

Any advice or scales/rifft actually improves your playing and that i could use to warm up and especially right hand things that could help me improve would be great.

Practise strumming one chord in different patterns. Even see how fast you can strum. EG : Strum down up slap down up slap (E major) - Up up up (A Minor).
Then do the same with picking.

Check out some short tutorial videos on youtube, there is some cool ideas lurking about there.

http://www.youtube.com/user/helisell

In order to better yourself you have to set up a system in which you practice certain skills. Start playing maybe a song you know well and really like, once you are warmed up play some scales and corresponding chords. Do this for about half an hour. Then you probably want to move on to learning a new song. so pick a song with a technique you are not very good at (ie sweep picking) that way you can include about 20 minutes of practicing how to sweep as well as learning your new song. Remember practicing new things is best when done SLOWLY, i suggest you get a metronome. You begin with the tempo in which you can play it perfectly without anymistakes. Then raise it one notch until perfect, repeat until you reach the desired tempo