HELP new to analog HELP with Rega

Hello,

I just bought an older Rega planar two 9the one with the wood surround. I am trying to get into analog. I have a few questions about set up and the sort. First the seller said it was coming with a 'new' RB-250 tone arm. I'm not sure how to tell if it's the new or old one I have. Mine has green markings on the weight. Also a green three position switch on the tone base. (what is this?) This 'new' arm seems to have had some soldering done to the connector that attached to the cartridge if this wire comes undone again am I screwed? On the subject of wires..I didn't expect Regas to come with perminant crappy interconnects ....is there a cheap solution to this? (also supprised to see no ground wire)

I have a new Grado green cartridge I think this is a good match ? Any comments?

My main problem is when playing records? Lighter passages seem to slow down a bit and warble. They never sound faster. I think this is a belt problem because my house current is quite constant but Im not sure whats causing this? Is there anyplace to get generic belts for these that don't cost the 25$ that rega charges?

Lastly what is a good solution to cleaning used records. After several cleaning with basic record cleaner most of my records seem crackly and some a bit vailed??

Thanks for your time and patience !!